kselftest/arm64: mte: fix printf type warnings about longs

When checking MTE tags, we print some diagnostic messages when the tests
fail. Some variables uses there are "longs", however we only use "%x"
for the format specifier.

Update the format specifiers to "%lx", to match the variable types they
are supposed to print.

Fixes: f3b2a26c ("kselftest/arm64: Verify mte tag inclusion via prctl")
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240816153251.2833702-9-andre.przywara@arm.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>