feat(fwu): initialize FWU driver in BL2

Initialized FWU driver module in BL2 component under
build flag PSA_FWU_SUPPORT.

Change-Id: I08b191599835925c355981d695667828561b9a21
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/Makefile b/Makefile
index edc0d49..b4bebf1 100644
--- a/Makefile
+++ b/Makefile
@@ -746,6 +746,10 @@
     endif
 endif
 
+ifeq ($(PSA_FWU_SUPPORT),1)
+    $(info PSA_FWU_SUPPORT is an experimental feature)
+endif
+
 ifeq (${ARM_XLAT_TABLES_LIB_V1}, 1)
     ifeq (${ALLOW_RO_XLAT_TABLES}, 1)
         $(error "ALLOW_RO_XLAT_TABLES requires translation tables library v2")
@@ -959,6 +963,7 @@
         USE_SP804_TIMER \
         ENABLE_FEAT_RNG \
         ENABLE_FEAT_SB \
+        PSA_FWU_SUPPORT \
 )))
 
 $(eval $(call assert_numerics,\
@@ -1058,6 +1063,7 @@
         ENABLE_FEAT_SB \
         NR_OF_FW_BANKS \
         NR_OF_IMAGES_IN_FW_BANK \
+        PSA_FWU_SUPPORT \
 )))
 
 ifeq (${SANITIZE_UB},trap)