tests/functional: reduce tuxrun maxmem to work on 32-bit hosts

maxmem=4G is too large to address on 32-bit hosts, so reduce it
to 2G since the tuxrun tests don't actually need such an elevated
memory limit.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250228102738.3064045-5-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

tests/functional/test_ppc64_tuxrun.py

@@ -64,7 +64,7 @@ class TuxRunPPC64Test(TuxRunBaselineTest):
                          ',"index":1,"id":"pci.1"}')
         self.vm.add_args('-device', '{"driver":"spapr-vscsi","id":"scsi1"'
                          ',"reg":12288}')
-        self.vm.add_args('-m', '2G,slots=32,maxmem=4G',
+        self.vm.add_args('-m', '1G,slots=32,maxmem=2G',
                          '-object', 'memory-backend-ram,id=ram1,size=1G',
                          '-device', 'pc-dimm,id=dimm1,memdev=ram1')