rtl8812au-ct: fix compilation with GCC 15

rtl8812au-ct: fix compilation with GCC 15

GCC 15 enables -Wheader-guard and the kernel module build treats
warnings as errors, so the mismatched include guards in three driver
headers break the build:

  include/rtl8812a_sreset.h:20: error: header guard
  '_RTL88812A_SRESET_H_' followed by '#define' of a different macro
  [-Werror=header-guard]

Add a patch making each '#ifndef' match its '#define'. rtl8192e_sreset.h
was a copy/paste of the rtl8812a guard, so it gets its own
'_RTL8192E_SRESET_H_' name instead of duplicating '_RTL8812A_SRESET_H_'.

Assisted-by: Claude:claude-opus-4-8
Link: https://github.com/openwrt/openwrt/pull/23957
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>