fix #51818 lvm2 breakage, move to mkinitcpio running as pacman hook

PKGBUILD

@@ -6,7 +6,7 @@ pkgbase=linux               # Build stock -ARCH kernel
 #pkgbase=linux-custom       # Build kernel with a different name
 _srcname=linux-4.8
 pkgver=4.8.8
-pkgrel=1
+pkgrel=2
 arch=('i686' 'x86_64')
 url="http://www.kernel.org/"
 license=('GPL2')
@@ -18,6 +18,8 @@ source=("https://www.kernel.org/pub/linux/kernel/v4.x/${_srcname}.tar.xz"
         "https://www.kernel.org/pub/linux/kernel/v4.x/patch-${pkgver}.sign"
         # the main kernel config files
         'config' 'config.x86_64'
+        # pacman hook for initramfs regeneration
+        '80-linux.hook'
         # standard config files for mkinitcpio ramdisk
         'linux.preset'
         'change-default-console-loglevel.patch'
@@ -29,6 +31,7 @@ sha256sums=('3e9150065f193d3d94bcf46a1fe9f033c7ef7122ab71d75a7fb5a2f0c9a7e11a'
             'SKIP'
             '2ac8818414beb7dbacbd3ad450c516e6ada804827132a7132f63b8189e5f5151'
             '93a4ad4f6c7bb9296fddec436ed7477a5a5c11cf4d6e68482fa6610442cbcb1f'
+            '2d4424928ae3c5f63ee618b4685580f4bd24faf1778553dbd961f85a88ea0910'
             'f0d90e756f14533ee67afda280500511a62465b4f76adcc5effa95a40045179c'
             '1256b241cd477b265a3c2d64bdc19ffe3c9bbcee82ea3994c590c2c76e767d99')
 validpgpkeys=(
@@ -128,6 +131,9 @@ _package() {
     -e "s|fallback_image=.*|fallback_image=\"/boot/initramfs-${pkgbase}-fallback.img\"|" \
     -i "${pkgdir}/etc/mkinitcpio.d/${pkgbase}.preset"
 
+  # install pacman hook for initramfs regeneration
+  install -D -m644 "${srcdir}/80-linux.hook" "${pkgdir}/usr/share/libalpm/hooks/80-linux.hook"
+
   # remove build and source links
   rm -f "${pkgdir}"/lib/modules/${_kernver}/{source,build}
   # remove the firmware