Add openPOWER version string support

See VERSION.readme for more info
diff --git a/openpower/package/openpower-pnor/openpower-pnor.mk b/openpower/package/openpower-pnor/openpower-pnor.mk
index 8854207..3639e9c 100644
--- a/openpower/package/openpower-pnor/openpower-pnor.mk
+++ b/openpower/package/openpower-pnor/openpower-pnor.mk
@@ -30,6 +30,11 @@
 HOSTBOOT_IMAGE_DIR=$(STAGING_DIR)/hostboot_build_images/
 HOSTBOOT_BINARY_DIR = $(STAGING_DIR)/hostboot_binaries/
 OPENPOWER_PNOR_SCRATCH_DIR = $(STAGING_DIR)/openpower_pnor_scratch/
+OPENPOWER_VERSION_DIR = $(STAGING_DIR)/openpower_version
+
+# Subpackages we want to include in the version info (do not include openpower-pnor)
+OPENPOWER_VERSIONED_SUBPACKAGES = hostboot occ skiboot hostboot-binaries $(XML_PACKAGE) capp-ucode
+OPENPOWER_PNOR = openpower-pnor
 
 define OPENPOWER_PNOR_INSTALL_IMAGES_CMDS
         mkdir -p $(OPENPOWER_PNOR_SCRATCH_DIR)
@@ -44,7 +49,8 @@
             -sbe_binary_filename $(BR2_HOSTBOOT_BINARY_SBE_FILENAME) \
             -sbec_binary_filename $(BR2_HOSTBOOT_BINARY_SBEC_FILENAME) \
             -occ_binary_filename $(OCC_STAGING_DIR)/$(BR2_OCC_BIN_FILENAME) \
-            -capp_binary_filename $(BINARIES_DIR)/$(BR2_CAPP_UCODE_BIN_FILENAME)
+            -capp_binary_filename $(BINARIES_DIR)/$(BR2_CAPP_UCODE_BIN_FILENAME) \
+            -openpower_version_filename $(OPENPOWER_PNOR_VERSION_FILE)
 
         mkdir -p $(STAGING_DIR)/pnor/
         $(TARGET_MAKE_ENV) $(@D)/create_pnor_image.pl \
@@ -58,9 +64,12 @@
             -sbe_binary_filename $(BR2_HOSTBOOT_BINARY_SBE_FILENAME) \
             -sbec_binary_filename $(BR2_HOSTBOOT_BINARY_SBEC_FILENAME) \
             -occ_binary_filename $(OCC_STAGING_DIR)/$(BR2_OCC_BIN_FILENAME) \
-            -targeting_binary_filename $(BR2_OPENPOWER_TARGETING_ECC_FILENAME)
+            -targeting_binary_filename $(BR2_OPENPOWER_TARGETING_ECC_FILENAME) \
+            -openpower_version_filename $(OPENPOWER_PNOR_VERSION_FILE)
 
         $(INSTALL) $(STAGING_DIR)/pnor/$(BR2_OPENPOWER_PNOR_FILENAME) $(BINARIES_DIR)
 endef
 
 $(eval $(generic-package))
+# Generate openPOWER pnor version string by combining subpackage version string files
+$(eval $(call OPENPOWER_VERSION,$(OPENPOWER_PNOR)))