src/fccache.c: Fix define for HAVE_POSIX_FADVISE

Otherwise, there would be build errors in the following 2 cases:
* define HAVE_POSIX_FADVISE
Or:
* undef HAVE_POSIX_FADVISE
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>

src/fccache.c

@@ -976,7 +976,7 @@ FcDirCacheMapFd (FcConfig *config, int fd, struct stat *fd_stat, struct stat *di
     {
 #if defined(HAVE_MMAP) || defined(__CYGWIN__)
 	cache = mmap (0, fd_stat->st_size, PROT_READ, MAP_SHARED, fd, 0);
-#if (HAVE_POSIX_FADVISE) && defined(POSIX_FADV_WILLNEED)
+#if defined(HAVE_POSIX_FADVISE) && defined(POSIX_FADV_WILLNEED)
 	posix_fadvise (fd, 0, fd_stat->st_size, POSIX_FADV_WILLNEED);
 #endif
 	if (cache == MAP_FAILED)