Source the variant file in the verify script

If the variant file has defined mandatory input variables like IMG_ID
the verification script should not fail to find them.

This fixes #35

snf-image-host/common.sh.in

@@ -265,7 +265,10 @@ ganeti_os_main() {
     fi
 
     get_api20_arguments
+    source_variant
+}
 
+source_variant() {
     if [ -n "$OS_VARIANT" ]; then
         if [ ! -d "$VARIANTS_DIR" ]; then
             log_error "OS Variants directory $VARIANTS_DIR doesn't exist"

snf-image-host/verify

@@ -31,6 +31,8 @@ check_required() {
         eval $param=\"\$OSP_$param\"
     done
 
+    source_variant
+
     for var in $required_params; do
         if [ -z "${!var}" ]; then
              log_error "Missing OS API Parameter: ${var}"