Dump platform-defined regs in crash reporting

It is up to the platform to implement the new plat_crash_print_regs macro to
report all relevant platform registers helpful for troubleshooting.

plat_crash_print_regs merges or calls previously defined plat_print_gic_regs
and plat_print_interconnect_regs macros for each existing platforms.

NOTE: THIS COMMIT REQUIRES ALL PLATFORMS THAT ENABLE THE `CRASH_REPORTING`
BUILD FLAG TO MIGRATE TO USE THE NEW `plat_crash_print_regs()` MACRO. BY
DEFAULT, `CRASH_REPORTING` IS ENABLED IN DEBUG BUILDS FOR ALL PLATFORMS.

Fixes: arm-software/tf-issues#373

Signed-off-by: Gerald Lejeune <gerald.lejeune@st.com>
diff --git a/plat/arm/board/juno/include/plat_macros.S b/plat/arm/board/juno/include/plat_macros.S
index d2a88ed..bb42bca 100644
--- a/plat/arm/board/juno/include/plat_macros.S
+++ b/plat/arm/board/juno/include/plat_macros.S
@@ -33,10 +33,16 @@
 #include <cci_macros.S>
 #include <css_macros.S>
 
-/*
- * Required platform porting macros
- * (Provided by included headers)
- */
-
+	/* ---------------------------------------------
+	 * The below required platform porting macro
+	 * prints out relevant platform registers
+	 * whenever an unhandled exception is taken in
+	 * BL31.
+	 * ---------------------------------------------
+	 */
+	.macro plat_crash_print_regs
+	css_print_gic_regs
+	print_cci_regs
+	.endm
 
 #endif /* __PLAT_MACROS_S__ */