[Silabs] Open basic commissioning window on pb0 press and release

[jmartinez-silabs]

Problem:
There was still some old code in silabs example applications to restart the BLE advertisement on a button press.
However, it didn't amount to much as the commission window was closed.

Changes:
On pb0 short press and release, Open the basic commissioning window. This will also start the BLE advertisement.

Tested manually with an EFR32 with lighting-app.
Wait for the initial advertisement/commissioning window to close. Press PB0, validated the BLE advertisement restarts and that the commissioning can be complete.

[github-actions]

PR #22940: Size comparison from 46fd14a to dbbbc13

Decreases (2 builds for bl702)

platform	target	config	section	46fd14a	dbbbc13	change	% change
bl702	lighting-app	bl702	.debug_info	37899569	37899568	-1	-0.0
			.text	956554	956552	-2	-0.0
		bl702+rpc	.debug_info	41806178	41806177	-1	-0.0
			.text	1030254	1030252	-2	-0.0

Full report (8 builds for bl702, linux, mbed, telink)

platform	target	config	section	46fd14a	dbbbc13	change	% change
bl702	lighting-app	bl702		0	0	0	0.0
			(read only)	3262	3262	0	0.0
			(read/write)	1187963	1187963	0	0.0
			.bleromro	6296	6296	0	0.0
			.bleromrw	124	124	0	0.0
			.boot2	688	688	0	0.0
			.bss	67094	67094	0	0.0
			.bss_psram	29696	29696	0	0.0
			.comment	48	48	0	0.0
			.data	4272	4272	0	0.0
			.debug_abbrev	1506903	1506903	0	0.0
			.debug_aranges	133080	133080	0	0.0
			.debug_frame	486372	486372	0	0.0
			.debug_info	37899569	37899568	-1	-0.0
			.debug_line	5252792	5252792	0	0.0
			.debug_loc	3364396	3364396	0	0.0
			.debug_ranges	359104	359104	0	0.0
			.debug_str	3456111	3456111	0	0.0
			.hbn	509	509	0	0.0
			.hbn_noinit	260	260	0	0.0
			.init	342	342	0	0.0
			.init_array	144	144	0	0.0
			.psram	0	0	0	0.0
			.riscv.attributes	47	47	0	0.0
			.rodata	116536	116536	0	0.0
			.rsvd	3188	3188	0	0.0
			.shstrtab	293	293	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	564835	564835	0	0.0
			.symtab	171584	171584	0	0.0
			.tcm_data	36	36	0	0.0
			.tcmcode	3262	3262	0	0.0
			.text	956554	956552	-2	-0.0
		bl702+rpc		0	0	0	0.0
			(read only)	3262	3262	0	0.0
			(read/write)	1283883	1283883	0	0.0
			.bleromro	6296	6296	0	0.0
			.bleromrw	124	124	0	0.0
			.boot2	688	688	0	0.0
			.bss	75142	75142	0	0.0
			.bss_psram	29936	29936	0	0.0
			.comment	48	48	0	0.0
			.data	4800	4800	0	0.0
			.debug_abbrev	1644448	1644448	0	0.0
			.debug_aranges	140584	140584	0	0.0
			.debug_frame	511748	511748	0	0.0
			.debug_info	41806178	41806177	-1	-0.0
			.debug_line	5627327	5627327	0	0.0
			.debug_loc	3557140	3557140	0	0.0
			.debug_ranges	381560	381560	0	0.0
			.debug_str	3852011	3852011	0	0.0
			.hbn	509	509	0	0.0
			.hbn_noinit	260	260	0	0.0
			.init	342	342	0	0.0
			.init_array	160	160	0	0.0
			.psram	0	0	0	0.0
			.riscv.attributes	47	47	0	0.0
			.rodata	129928	129928	0	0.0
			.rsvd	3188	3188	0	0.0
			.shstrtab	293	293	0	0.0
			.stack	2048	2048	0	0.0
			.strtab	624008	624008	0	0.0
			.symtab	189392	189392	0	0.0
			.tcm_data	36	36	0	0.0
			.tcmcode	3262	3262	0	0.0
			.text	1030254	1030252	-2	-0.0
linux	chip-tool-ipv6only	arm64	(read only)	10422220	10422220	0	0.0
			(read/write)	706257	706257	0	0.0
			.bss	33953	33953	0	0.0
			.data	2864	2864	0	0.0
			.data.rel.ro	650560	650560	0	0.0
			.dynamic	560	560	0	0.0
			.got	13904	13904	0	0.0
			.init	24	24	0	0.0
			.init_array	208	208	0	0.0
			.rodata	517372	517372	0	0.0
			.text	8250868	8250868	0	0.0
	thermostat-no-ble	arm64	(read only)	2387428	2387428	0	0.0
			(read/write)	143649	143649	0	0.0
			.bss	55361	55361	0	0.0
			.data	1912	1912	0	0.0
			.data.rel.ro	77208	77208	0	0.0
			.dynamic	560	560	0	0.0
			.got	5184	5184	0	0.0
			.init	24	24	0	0.0
			.init_array	440	440	0	0.0
			.rodata	143644	143644	0	0.0
			.text	2001488	2001488	0	0.0
mbed	lock-app	CY8CPROTO_062_4343W+release	(read only)	6224	6224	0	0.0
			(read/write)	2455648	2455648	0	0.0
			.bss	215044	215044	0	0.0
			.data	5872	5872	0	0.0
			.text	1418292	1418292	0	0.0
telink	light-switch-app	tlsr9518adk80d	(read/write)	814500	814500	0	0.0
			bss	72172	72172	0	0.0
			noinit	43488	43488	0	0.0
			text	574574	574574	0	0.0
	lighting-app	tlsr9518adk80d	(read/write)	836604	836604	0	0.0
			bss	73028	73028	0	0.0
			noinit	43488	43488	0	0.0
			text	592794	592794	0	0.0
	ota-requestor-app	tlsr9518adk80d	(read/write)	844556	844556	0	0.0
			bss	73936	73936	0	0.0
			noinit	43488	43488	0	0.0
			text	598976	598976	0	0.0