Use compgen to gather components in all.sh

Signed-off-by: Gowtham Suresh Kumar <gowtham.sureshkumar@arm.com>
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index f1da9d2..ad31e5c 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -191,9 +191,7 @@
 
     # Gather the list of available components. These are the functions
     # defined in this script whose name starts with "component_".
-    # Parse the script with sed. This way we get the functions in the order
-    # they are defined.
-    ALL_COMPONENTS=$(sed -n 's/^ *component_\([0-9A-Z_a-z]*\) *().*/\1/p' <"$0")
+    ALL_COMPONENTS=$(compgen -A function component_ | sed 's/component_//')
 
     # Exclude components that are not supported on this platform.
     SUPPORTED_COMPONENTS=