COMPMID-2486: Remove/add disabled compiler warnings

Removed the following flags:
-Wno-vla
-Wno-strict-overflow

Added:
-Wformat-security

Change-Id: I49eb3d724e14db796e543164295674617c37cb65
Signed-off-by: Michalis Spyrou <michalis.spyrou@arm.com>
Reviewed-on: https://review.mlplatform.org/c/2109
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
diff --git a/utils/ImageLoader.h b/utils/ImageLoader.h
index f37ffa2..c03cbdf 100644
--- a/utils/ImageLoader.h
+++ b/utils/ImageLoader.h
@@ -33,6 +33,7 @@
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wswitch-default"
+#pragma GCC diagnostic ignored "-Wstrict-overflow"
 #include "stb/stb_image.h"
 #pragma GCC diagnostic pop