refactor(measured boot): remove platform calls from Event Log driver

Currently, the Event Log driver does platform layer work by invoking
a few platform functions in the 'event_log_finalise' call. Doing
platform work does not seem to be the driver's responsibility, hence
moved 'event_log_finalise' function's implementation to the platform
layer.

Alongside, introduced few Event Log driver functions and done
some cosmetic changes.

Change-Id: I486160e17e5b0677c734fd202af7ccd85476a551
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/include/plat/arm/common/plat_arm.h b/include/plat/arm/common/plat_arm.h
index 57e6953..5765226 100644
--- a/include/plat/arm/common/plat_arm.h
+++ b/include/plat/arm/common/plat_arm.h
@@ -250,9 +250,8 @@
 int arm_get_mbedtls_heap(void **heap_addr, size_t *heap_size);
 
 #if MEASURED_BOOT
-int arm_set_tos_fw_info(uintptr_t config_base, uintptr_t log_addr,
-			size_t log_size);
-int arm_set_nt_fw_info(uintptr_t config_base,
+int arm_set_tos_fw_info(uintptr_t log_addr, size_t log_size);
+int arm_set_nt_fw_info(
 /*
  * Currently OP-TEE does not support reading DTBs from Secure memory
  * and this option should be removed when feature is supported.