build: remove LEVELDB_IS_BIG_ENDIAN

Author: fanquake

cmake/leveldb.cmake

@@ -60,7 +60,6 @@ target_compile_definitions(leveldb
     HAVE_FULLFSYNC=$<BOOL:${HAVE_FULLFSYNC}>
     HAVE_O_CLOEXEC=$<BOOL:${HAVE_O_CLOEXEC}>
     FALLTHROUGH_INTENDED=[[fallthrough]]
-    LEVELDB_IS_BIG_ENDIAN=$<STREQUAL:${CMAKE_CXX_BYTE_ORDER},BIG_ENDIAN>
     $<$<NOT:$<BOOL:${WIN32}>>:LEVELDB_PLATFORM_POSIX>
     $<$<BOOL:${WIN32}>:LEVELDB_PLATFORM_WINDOWS>
     $<$<BOOL:${WIN32}>:_UNICODE;UNICODE>