arm64: KGDB: Add KGDB config

Add HAVE_ARCH_KGDB for arm64 Kconfig
Signed-off-by: NVijaya Kumar K <Vijaya.Kumar@caviumnetworks.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

arch/arm64/Kconfig

@@ -26,6 +26,7 @@ config ARM64
 	select GENERIC_TIME_VSYSCALL
 	select HARDIRQS_SW_RESEND
 	select HAVE_ARCH_JUMP_LABEL
+	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_DEBUG_BUGVERBOSE
 	select HAVE_DEBUG_KMEMLEAK