Avoid failing on 64-bit ARM

Affects systems like the NVIDIA DRIVE CX. This did not show up so far
because there was no error when Q_PROCESSOR_ARM was not set.

Task-number: QTBUG-53493
Change-Id: I107155b6dc1a881eca6f57374ad8db4458875243
Reviewed-by: Dominik Holland <dominik.holland@pelagicore.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/global/qprocessordetection.h

@@ -107,7 +107,7 @@
 #    define Q_PROCESSOR_ARM __TARGET_ARCH_ARM
 #  elif defined(_M_ARM) && _M_ARM > 1
 #    define Q_PROCESSOR_ARM _M_ARM
-#  elif defined(__ARM64_ARCH_8__)
+#  elif defined(__ARM64_ARCH_8__) || defined(__aarch64__)
 #    define Q_PROCESSOR_ARM 8
 #  elif defined(__ARM_ARCH_7__) \
       || defined(__ARM_ARCH_7A__) \