eclass/coreos-kernel: fix indentation and codestyle

Signed-off-by: Daniel Zatovic <daniel.zatovic@gmail.com>

Author: danzatt

sdk_container/src/third_party/coreos-overlay/eclass/coreos-kernel.eclass

@@ -154,7 +154,7 @@ get_sig_key() {
 		die "MODULES_SIGN_KEY variable is different than MODULE_SIG_KEY in kernel config."
 	fi
 
-	echo $sig_key
+	echo "$sig_key"
 }
 
 validate_sig_key() {
@@ -170,13 +170,13 @@ setup_keys() {
 	echo "Preparing keys at $sig_key"
 
 	if [[ ${COREOS_OFFICIAL:-0} -eq 0 ]]; then
-          # Allow portage sandbox to write to the module signing key directory,
-          # which is in home for unofficial builds
-          addwrite "${MODULE_SIGNING_KEY_DIR}"
-        fi
+		# Allow portage sandbox to write to the module signing key directory,
+		# which is in home for unofficial builds
+		addwrite "${MODULE_SIGNING_KEY_DIR}"
+	fi
 
-	mkdir -p $MODULE_SIGNING_KEY_DIR
-	pushd $MODULE_SIGNING_KEY_DIR
+	mkdir -p "$MODULE_SIGNING_KEY_DIR"
+	pushd "$MODULE_SIGNING_KEY_DIR"
 
 	mkdir -p gen_certs || die
 	# based on the default config the kernel auto-generates