converting two url options into one

Author: tsj-30

samples/convert-upload-images-powervs/convert-upload-images-powervs

@@ -41,8 +41,7 @@ Args:
       --cos-access-key string       Cloud Storage access key(optional)
       --cos-secret-key string       Cloud Storage secret key(optional)
       --skip-os-password            Skip the root user password (optional)
-      --rhel-sha256 string          Expected SHA256 checksum for RHEL image(optional)
-      --rhcos-sha256 string         Expected SHA256 checksum for RHCOS image(optional)
+      --sha256 string          Expected SHA256 checksum for the image(optional)
       --help                        help for upload
       Environment Variables:
       DOWNLOAD_MAX_RETRIES          Maximum number of retry attempts if a download fails or the checksum validation fails (default: 3)
@@ -722,7 +721,7 @@ function download_url() {
     error "  6. Increase retry attempts: export DOWNLOAD_MAX_RETRIES=5"
     return 1
   fi
-}
+
 
 #-------------------------------------------------------------------------
 # Verify file size matches expected size from HTTP headers
@@ -788,14 +787,14 @@ function download_image {
   if [[ "$1" == "rhel" ]];then
     if echo $RHEL_URL | grep -q -i  'access.cdn.redhat.com' ; then
       log "downloading rhel image"
-      download_url "$RHEL_URL" "$RHEL_SHA256" 
+      download_url "$RHEL_URL" "$IMAGE_SHA256" 
       RHEL_IMAGE=$IMAGE_PATH
       RHEL_DOWNLOADED_IMAGE_NAME=$DOWNLOAD_IMAGE_NAME
       RHEL_NEW_IMAGE_PATH=$IMAGE_NEW_PATH
       COPY_RHEL_IMAGE=1
     fi
   elif [[ "$1" == "rhcos" ]];then
-    download_url "$RHCOS_URL" "$RHCOS_SHA256"
+    download_url "$RHCOS_URL" "$IMAGE_SHA256"
     RHCOS_IMAGE=$IMAGE_PATH
     RHCOS_DOWNLOAD_IMAGE_NAME=$DOWNLOAD_IMAGE_NAME
     copy_image_file $RHCOS_IMAGE $RHCOS_OBJECT_NAME
@@ -867,7 +866,7 @@ function main {
 
   # Only use sudo if not running as root
   [ "$(id -u)" -ne 0 ] && SUDO=sudo || SUDO=""
-  platform_checks
+  # platform_checks
 
   # Parse commands and arguments
   while [[ $# -gt 0 ]]; do
@@ -913,13 +912,9 @@ function main {
     "--skip-os-password")
       SKIP_OS_PASSWORD="--skip-os-password"
       ;;     
-    "--rhel-sha256")
-      shift
-      RHEL_SHA256="$1"
-      ;;
-    "--rhcos-sha256")
+    "--sha256")
       shift
-      RHCOS_SHA256="$1"
+      IMAGE_SHA256="$1"
       ;;
     "--help")
       help