Apply TBBR naming convention to the fip_create options

The fip_create tool specifies images in the command line using the
ARM TF naming convention (--bl2, --bl31, etc), while the cert_create
tool uses the TBBR convention (--tb-fw, --soc-fw, etc). This double
convention is confusing and should be aligned.

This patch updates the fip_create command line options to follow the
TBBR naming convention. Usage examples in the User Guide have been
also updated.

NOTE: users that build the FIP by calling the fip_create tool directly
from the command line must update the command line options in their
scripts. Users that build the FIP by invoking the main ARM TF Makefile
should not notice any difference.

Change-Id: I84d602630a2585e558d927b50dfde4dd2112496f
diff --git a/plat/arm/css/common/css_common.mk b/plat/arm/css/common/css_common.mk
index aabcb46..6a8773d 100644
--- a/plat/arm/css/common/css_common.mk
+++ b/plat/arm/css/common/css_common.mk
@@ -52,7 +52,7 @@
 				plat/arm/css/common/css_topology.c
 
 ifneq (${TRUSTED_BOARD_BOOT},0)
-$(eval $(call FWU_FIP_ADD_IMG,SCP_BL2U,--scp_bl2u))
+$(eval $(call FWU_FIP_ADD_IMG,SCP_BL2U,--scp-fwu-cfg))
 endif
 
 ifneq (${RESET_TO_BL31},0)
@@ -61,7 +61,7 @@
 endif
 
 # Subsystems require a SCP_BL2 image
-$(eval $(call FIP_ADD_IMG,SCP_BL2,--scp_bl2))
+$(eval $(call FIP_ADD_IMG,SCP_BL2,--scp-fw))
 
 # Enable option to detect whether the SCP ROM firmware in use predates version
 # 1.7.0 and therefore, is incompatible.