modules: hostap: remove select FILE_SYSTEM

Remove `select FILE_SYSTEM` from `WIFI_NM_WPA_SUPPLICANT`, originally
added in 3fc932c. The selection is not required by any tests, and does
not appear to be used by any code in the module.

Signed-off-by: Jordan Yates <jordan@embeint.com>

Author: JordanYates

modules/hostap/Kconfig

@@ -10,7 +10,6 @@ config WIFI_NM_WPA_SUPPLICANT
 	select POSIX_TIMERS
 	select POSIX_SIGNALS
 	select POSIX_API
-	select FILE_SYSTEM
 	select NET_SOCKETS
 	select NET_SOCKETS_PACKET
 	select NET_SOCKETPAIR