test(fvp): add a test to exercise reclaiming init code feature

Owing to the reason explained in patch [1], the feature to reclaim
BL31 init code has been disabled by default for FVP platform.

This patch upgrades an existing test config to exercise this feature
and adds a new TF build config with RECLAIM_INIT_CODE enabled
explicitly.

[1] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/14438

Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Change-Id: Ieb785feaf5b90e349494109d14b4446784eebe4d
diff --git a/tf_config/fvp-reclaim-init-code b/tf_config/fvp-reclaim-init-code
new file mode 100644
index 0000000..eec8df2
--- /dev/null
+++ b/tf_config/fvp-reclaim-init-code
@@ -0,0 +1,3 @@
+CROSS_COMPILE=aarch64-none-elf-
+PLAT=fvp
+RECLAIM_INIT_CODE=1