test: lib: Use CONFIG_64BIT to detect 64 bit compile

Should use CONFIG_64BIT to detect a 64 bit compile and not
CONFIG_PHYS_64BIT. This allows more platforms to run the
full test code.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Andrew Goodbody <andrew.goodbody@linaro.org>
diff --git a/test/lib/str.c b/test/lib/str.c
index e620453..48351ab 100644
--- a/test/lib/str.c
+++ b/test/lib/str.c
@@ -224,13 +224,13 @@
 	ut_asserteq_str("4294967295", simple_itoa(0xffffffff));
 
 	/* Use #ifdef here to avoid a compiler warning on 32-bit machines */
-#ifdef CONFIG_PHYS_64BIT
+#ifdef CONFIG_64BIT
 	if (sizeof(ulong) == 8) {
 		ut_asserteq_str("9223372036854775807",
 				simple_itoa((1UL << 63) - 1));
 		ut_asserteq_str("18446744073709551615", simple_itoa(-1));
 	}
-#endif /* CONFIG_PHYS_64BIT */
+#endif /* CONFIG_64BIT */
 
 	return 0;
 }
@@ -244,13 +244,13 @@
 	ut_asserteq_str("ffffffff", simple_xtoa(0xffffffff));
 
 	/* Use #ifdef here to avoid a compiler warning on 32-bit machines */
-#ifdef CONFIG_PHYS_64BIT
+#ifdef CONFIG_64BIT
 	if (sizeof(ulong) == 8) {
 		ut_asserteq_str("7fffffffffffffff",
 				simple_xtoa((1UL << 63) - 1));
 		ut_asserteq_str("ffffffffffffffff", simple_xtoa(-1));
 	}
-#endif /* CONFIG_PHYS_64BIT */
+#endif /* CONFIG_64BIT */
 
 	return 0;
 }