Allow skipping the distribution check

This is useful for development on new distributions.

Signed-off-by: Julian Stecklina <julian.stecklina@cyberus-technology.de>

kpatch-build/kpatch-build

@@ -51,6 +51,7 @@ RELEASE_FILE=/etc/os-release
 DEBUG=0
 SKIPCLEANUP=0
 SKIPCOMPILERCHECK=0
+SKIPDISTROCHECK=0
 ARCH_KCFLAGS=""
 DEBUG_KCFLAGS=""
 declare -a PATCH_LIST
@@ -733,13 +734,15 @@ usage() {
 	echo "		--skip-cleanup          Skip post-build cleanup" >&2
 	echo "		--skip-compiler-check   Skip compiler version matching check" >&2
 	echo "		                        (not recommended)" >&2
+	echo "          --skip-distro-check     Skip checking for a compatible distribution" >&2
+	echo "                                  (not recommended)" >&2
 }
 
 if ! command -v gawk &> /dev/null; then
 	die "gawk not installed"
 fi
 
-options="$(getopt -o ha:r:s:c:v:j:t:n:o:dR -l "help,archversion:,sourcerpm:,sourcedir:,config:,vmlinux:,jobs:,target:,name:,output:,oot-module:,oot-module-src:,debug,skip-gcc-check,skip-compiler-check,skip-cleanup,non-replace" -- "$@")" || die "getopt failed"
+options="$(getopt -o ha:r:s:c:v:j:t:n:o:dR -l "help,archversion:,sourcerpm:,sourcedir:,config:,vmlinux:,jobs:,target:,name:,output:,oot-module:,oot-module-src:,debug,skip-gcc-check,skip-compiler-check,skip-cleanup,non-replace,skip-distro-check" -- "$@")" || die "getopt failed"
 
 eval set -- "$options"
 
@@ -821,6 +824,10 @@ while [[ $# -gt 0 ]]; do
 		echo "WARNING: Skipping compiler version matching check (not recommended)"
 		SKIPCOMPILERCHECK=1
 		;;
+	--skip-distro-check)
+		echo "WARNING: Skipping distribution check (not recommended)"
+		SKIPDISTROCHECK=1
+		;;
 	*)
 		[[ "$1" = "--" ]] && shift && continue
 		[[ ! -f "$1" ]] && die "patch file '$1' not found"
@@ -1106,7 +1113,7 @@ else
 		sed -i "s/^SUBLEVEL.*/${sublevel}/" "$KERNEL_SRCDIR/Makefile" || die
 		echo "$ARCHVERSION" > "$VERSIONFILE" || die
 	else
-		die "Unsupported distribution"
+		[[ "$SKIPDISTROCHECK" -eq 0 ]] && die "Unsupported distribution"
 	fi
 fi