[llvm-lit] Add sparc64 to the list of BE triple (llvm#166113)

Linux uses `sparc64` triple name on 64-bit SPARCs.
This should fix the test failure in discriminated-union.ll.

Author: koachan

llvm/test/lit.cfg.py

@@ -474,7 +474,7 @@ def enable_ptxas(ptxas_executable):
 config.available_features.add("host-byteorder-" + sys.byteorder + "-endian")
 if config.target_triple:
     if re.match(
-        r"(aarch64_be|arc|armeb|bpfeb|lanai|m68k|mips|mips64|powerpc|powerpc64|sparc|sparcv9|s390x|s390|tce|thumbeb)-.*",
+        r"(aarch64_be|arc|armeb|bpfeb|lanai|m68k|mips|mips64|powerpc|powerpc64|sparc|sparcv9|sparc64|s390x|s390|tce|thumbeb)-.*",
         config.target_triple,
     ):
         config.available_features.add("target-byteorder-big-endian")