juno: Optimization level changed for Juno build

The transport layer based fast channel implementation is causing
Juno ramfw to be oversized which is causing boot failure.

This patch changes the optimization level of Juno build from default
Og to O2 to reduce the code size.

Signed-off-by: Md Golam Tanvir Zim <mdgolamtanvir.zim@arm.com>
Change-Id: I30bb32e49cb3dd8518b8eb8781c4892ca0fbb911
diff --git a/scp_config/juno-scmiv2 b/scp_config/juno-scmiv2
index da3b331..1644c1e 100644
--- a/scp_config/juno-scmiv2
+++ b/scp_config/juno-scmiv2
@@ -8,3 +8,4 @@
 EXTRA_CONFIG_ARGS+=-DSCP_ENABLE_DEBUG_UNIT=OFF
 EXTRA_CONFIG_ARGS+=-DSCP_ENABLE_RESOURCE_PERMISSIONS=OFF
 EXTRA_CONFIG_ARGS+=-DSCP_LOG_LEVEL=CRIT
+EXTRA_CONFIG_ARGS+=-DCMAKE_C_FLAGS_DEBUG=-Os