Fix PRIx64 being interpreted as C++11 user-defined literal suffix

[CrackedMatter]

It seems to only happen when targeting Android:

In file included from /home/redacted/funchook/test/test_cpp.cpp:6:
/home/redacted/funchook/test/unit_test.h:36:100: error: invalid suffix on literal; C++11 requires a space between literal and identifier [-Wreserved-user-defined-literal]
#define ASSERT_EQUAL_UINT64(expected, actual, funchook, ...) ASSERT_EQUAL_WITH_TYPE(uint64_t, "0x%"PRIx64, expected, actual, funchook, __VA_ARGS__)
                                                                                                   ^