configure: Fix arch detection for GDB_HAS_MTE

GDB_HAS_MTE must only be set if GDB supports the aarch64 arch, so the
test if "aarch64" string is present must be against GDB-related
'$gdb_arches' variable and not against '$arch' variable.

Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Message-Id: <20240804161850.2646299-2-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240813202329.1237572-4-alex.bennee@linaro.org>
1 file changed