qemu-system-mips needs a couple of semihosting fixes

[FlyGoat]

A couple of fixes are required to be backported get MIPS's semihosting work with QEMU shipped by the SDK.

List:
https://gitlab.com/qemu-project/qemu/-/commit/8ec7e3c53d48c61e31dd251b84a2b8190a14542d
https://gitlab.com/qemu-project/qemu/-/commit/7ba6e53a9ddf9b4ae04ad5fc658105440889cf17
https://gitlab.com/qemu-project/qemu/-/commit/6863e92d04c9ba23cbf7c0c1498e977c646e1faf
https://gitlab.com/qemu-project/qemu/-/commit/d53a3ed44605f7f070add30729e93bc7971ff6b1
https://gitlab.com/qemu-project/qemu/-/commit/3d748e41c759c7d207806b136be7694cfe2b6d65
https://gitlab.com/qemu-project/qemu/-/commit/18639a28bb313195308a97cacb6aa6a418fd73db
https://gitlab.com/qemu-project/qemu/-/commit/ea4210600db3c5721f90d46d9ad9ece120010041
https://gitlab.com/qemu-project/qemu/-/commit/412411b352d4b9226e5a506fdb6cadd17b83ba4a
https://gitlab.com/qemu-project/qemu/-/commit/3bb45bbc6fa59f35ab42e39ea4f4bcf67fea8d5f
https://gitlab.com/qemu-project/qemu/-/commit/b10ccec10096a27bb3b99a7291d5a3d5c826a1f3
https://gitlab.com/qemu-project/qemu/-/commit/b10ccec10096a27bb3b99a7291d5a3d5c826a1f3

They are almost all changes done to target/mips/tcg/system/mips-semi.c post 7.1 release point.