Secure Boot: Flag op-build version as production signed when applicable

- Add -prod extension to op-build version when production signed
diff --git a/openpower/package/pkg-versions.mk b/openpower/package/pkg-versions.mk
index 9a37bbb..be50245 100644
--- a/openpower/package/pkg-versions.mk
+++ b/openpower/package/pkg-versions.mk
@@ -134,7 +134,7 @@
 
 UPPER_CASE_PKG = $(call UPPERCASE,$(1))
 $$(UPPER_CASE_PKG)_VERSION_FILE = $$(OPENPOWER_VERSION_DIR)/$(1).version.txt
-
+UPPER_CASE_SIGN_MODE = $(call UPPERCASE,$$(BR2_OPENPOWER_SECUREBOOT_SIGN_MODE))
 
 $$(eval $$(foreach pkg,$$(OPENPOWER_VERSIONED_SUBPACKAGES), \
 		$$(call OPENPOWER_SUBPACKAGE_VERSION,$$(pkg),$$(call UPPERCASE,$$(pkg)))))
@@ -168,6 +168,11 @@
 	>> $$($$(UPPER_CASE_PKG)_VERSION_FILE); \
 fi
 
+# Flag whether op-build is production signed
+if [ "$$(UPPER_CASE_SIGN_MODE)" == 'PRODUCTION' ]; then \
+	echo -n "-prod" >> $$($$(UPPER_CASE_PKG)_VERSION_FILE); \
+fi
+
 # Add new line to $$($$(UPPER_CASE_PKG)_VERSION_FILE)
 echo "" >> $$($$(UPPER_CASE_PKG)_VERSION_FILE);