kernel: bump 5.15 to 5.15.125

1. Add new symbols to generic config
2. Bump kernel
   Changelog: https://lore.kernel.org/stable/2023080818-groin-gradient-a031@gregkh/

   All patches automatically rebased.

Signed-off-by: John Audia <therealgraysky@proton.me>
[Refreshed on top of OpenWrt 23.05]
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit daed3322d3)

target/linux/ramips/patches-5.15/314-MIPS-add-bootargs-override-property.patch

@@ -17,7 +17,7 @@ Signed-off-by: David Bauer <mail@david-bauer.net>
 
 --- a/arch/mips/kernel/setup.c
 +++ b/arch/mips/kernel/setup.c
-@@ -545,8 +545,28 @@ static int __init bootcmdline_scan_chose
+@@ -547,8 +547,28 @@ static int __init bootcmdline_scan_chose
  
  #endif /* CONFIG_OF_EARLY_FLATTREE */
  
@@ -46,7 +46,7 @@ Signed-off-by: David Bauer <mail@david-bauer.net>
  	bool dt_bootargs = false;
  
  	/*
-@@ -560,6 +580,14 @@ static void __init bootcmdline_init(void
+@@ -562,6 +582,14 @@ static void __init bootcmdline_init(void
  	}
  
  	/*