Add EL3_EXCEPTION_HANDLING to build command line

Commit 21b818c0

 (BL31: Introduce
Exception Handling Framework) introduced the build option
EL3_EXCEPTION_HANDLING, but missed to pass that to the build command
line. This patch fixes that.

Change-Id: I0a1be2c7b41a81e748ad7d6cf795aab7f6d19193
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>

Makefile

@@ -481,6 +481,7 @@ $(eval $(call assert_boolean,CTX_INCLUDE_AARCH32_REGS))
 $(eval $(call assert_boolean,CTX_INCLUDE_FPREGS))
 $(eval $(call assert_boolean,DEBUG))
 $(eval $(call assert_boolean,DISABLE_PEDANTIC))
+$(eval $(call assert_boolean,EL3_EXCEPTION_HANDLING))
 $(eval $(call assert_boolean,ENABLE_AMU))
 $(eval $(call assert_boolean,ENABLE_ASSERTIONS))
 $(eval $(call assert_boolean,ENABLE_PLAT_COMPAT))
@@ -524,6 +525,7 @@ $(eval $(call add_define,ARM_GIC_ARCH))
 $(eval $(call add_define,COLD_BOOT_SINGLE_CPU))
 $(eval $(call add_define,CTX_INCLUDE_AARCH32_REGS))
 $(eval $(call add_define,CTX_INCLUDE_FPREGS))
+$(eval $(call add_define,EL3_EXCEPTION_HANDLING))
 $(eval $(call add_define,ENABLE_AMU))
 $(eval $(call add_define,ENABLE_ASSERTIONS))
 $(eval $(call add_define,ENABLE_PLAT_COMPAT))