Update Arch kernel to v5.15.12

pkg/arch/kernel/PKGBUILD

@@ -2,7 +2,7 @@
 # Maintainer: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
 
 pkgbase=linux-surface
-pkgver=5.15.11.arch2
+pkgver=5.15.12.arch1
 pkgrel=1
 pkgdesc='Linux'
 _shortver=${pkgver%.*}