scripts: add a prettier version of autolocalversion

Enable CONFIG_LOCALVERSION_COMMIT_SHA if you want to see kernel version like this:
- before : 4.14.176-iMMENSITY-gb0d7253a
- after  : 4.14.176-iMMENSITY//4f70b3a2d0

Co-Authored-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
Signed-off-by: Yaroslav Furman <yaro330@gmail.com>
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>

arch/arm64/configs/raphael_defconfig

@@ -51,6 +51,7 @@ CONFIG_CROSS_COMPILE=""
 # CONFIG_COMPILE_TEST is not set
 CONFIG_LOCALVERSION="-iMMENSITY"
 CONFIG_LOCALVERSION_AUTO=y
+CONFIG_LOCALVERSION_COMMIT_SHA=y
 CONFIG_DEFAULT_HOSTNAME="(none)"
 CONFIG_SWAP=y
 # CONFIG_SYSVIPC is not set

init/Kconfig

@@ -115,6 +115,15 @@ config LOCALVERSION_AUTO
 
 	  which is done within the script "scripts/setlocalversion".)
 
+config LOCALVERSION_COMMIT_SHA
+	bool "Leave only commit sha"
+	default y
+	depends on LOCALVERSION_AUTO
+	depends on !COMPILE_TEST
+	help
+	  A cleaner version of LOCALVERSION_AUTO, contains
+	  commit sha of HEAD.
+
 config HAVE_KERNEL_GZIP
 	bool
 

scripts/setlocalversion

@@ -47,6 +47,13 @@ scm_version()
 	if test -z "$(git rev-parse --show-cdup 2>/dev/null)" &&
 	   head=`git rev-parse --verify --short HEAD 2>/dev/null`; then
 
+		# get commit sha and leave.
+		if test "$CONFIG_LOCALVERSION_COMMIT_SHA" = "y"; then
+			last_commit=$(git rev-parse --verify --short=10 HEAD)
+			printf '%s' "//$last_commit"
+			return
+		fi
+
 		# If we are at a tagged commit (like "v2.6.30-rc6"), we ignore
 		# it, because this version is defined in the top level Makefile.
 		if [ -z "`git describe --exact-match 2>/dev/null`" ]; then