FWU: Pass client cookie to FWU_SMC_UPDATE_DONE

The current FWU_SMC_UPDATE_DONE implementation incorrectly passes
an unused framework cookie through to the 1st argument in the
platform function `bl1_plat_fwu_done`. The intent is to allow
the SMC caller to pass a cookie through to this function.

This patch fixes FWU_SMC_UPDATE_DONE to pass x1 from the caller
through to `bl1_plat_fwu_done`. The argument names are updated
for clarity.

Upstream platforms currently do not use this argument so no
impact is expected.

Change-Id: I107f4b51eb03e7394f66d9a534ffab1cbc09a9b2
diff --git a/plat/arm/board/juno/juno_bl1_setup.c b/plat/arm/board/juno/juno_bl1_setup.c
index 61a5738..e805c9a 100644
--- a/plat/arm/board/juno/juno_bl1_setup.c
+++ b/plat/arm/board/juno/juno_bl1_setup.c
@@ -72,7 +72,7 @@
 /*******************************************************************************
  * On Juno clear SYS_NVFLAGS and wait for watchdog reset.
  ******************************************************************************/
-__dead2 void bl1_plat_fwu_done(void *cookie, void *rsvd_ptr)
+__dead2 void bl1_plat_fwu_done(void *client_cookie, void *reserved)
 {
 	unsigned int *nv_flags_clr = (unsigned int *)
 			(V2M_SYSREGS_BASE + V2M_SYS_NVFLAGSCLR);