change uvwasi_linkcount_t to uint64_t

Refs: WebAssembly/WASI#127

Author: cjihrig

README.md

@@ -1918,7 +1918,7 @@ Members:
 
     The address and length of the buffer to be filled.
 
-### <a href="#linkcount" name="linkcount"></a>`uvwasi_linkcount_t` (`uint32_t`)
+### <a href="#linkcount" name="linkcount"></a>`uvwasi_linkcount_t` (`uint64_t`)
 
 Number of hard links to an inode.
 

include/wasi_types.h

@@ -155,7 +155,7 @@ typedef struct uvwasi_iovec_s {
   size_t buf_len;
 } uvwasi_iovec_t;
 
-typedef uint32_t uvwasi_linkcount_t;
+typedef uint64_t uvwasi_linkcount_t;
 
 typedef uint32_t uvwasi_lookupflags_t;           /* Bitfield */
 #define UVWASI_LOOKUP_SYMLINK_FOLLOW (1 << 0)