civetweb: remove obsolete code

This code has gone unmaintained and bugs continue to be reported
against it. We do not have the resources as a project to maintain this
in "odd fixes" mode, and nobody has stepped up to maintain it [1], so
sadly this must be removed for now.

If anyone would like to see civetweb supported in upstream Zephyr
again, they are welcome to add it back, as long as they promise to
maintain it going forward.

Many thanks to everyone who has contributed to civetweb support in
Zephyr while it was here. So long and thanks for all the fish.

Fixes: zephyrproject-rtos#45807
Fixes: zephyrproject-rtos#43910

[1] https://lists.zephyrproject.org/g/devel/message/8466

Signed-off-by: Martí Bolívar <marti.bolivar@nordicsemi.no>

CODEOWNERS

@@ -666,7 +666,6 @@
 /samples/net/mqtt_publisher/              @rlubos
 /samples/net/sockets/coap_*/              @rlubos
 /samples/net/sockets/                     @rlubos @tbursztyka @pfalcon
-/samples/net/*civetweb*                   @Nukersson
 /samples/sensor/                          @MaureenHelm
 /samples/shields/                         @avisconti
 /samples/subsys/logging/                  @nordic-krch @jakub-uC

MAINTAINERS.yml

@@ -1926,16 +1926,6 @@ West:
         - manifest-canopennode
         - "area: CAN"
 
-"West project: civetweb":
-    status: obsolete
-    files:
-        - samples/net/civetweb/
-        - modules/Kconfig.civetweb
-    labels:
-        - manifest-civetweb
-        - "area: Networking"
-        - "area: civetweb"
-
 "West project: cmsis":
     status: maintained
     maintainers:

modules/Kconfig

@@ -9,7 +9,6 @@ comment "Optional modules. Make sure they're installed, via the project manifest
 
 source "modules/Kconfig.altera"
 source "modules/Kconfig.atmel"
-source "modules/Kconfig.civetweb"
 source "modules/Kconfig.cmsis"
 source "modules/Kconfig.cypress"
 source "modules/Kconfig.eos_s3"