repack.c: LLP64 compatibility, upcast unity for left shift

Visual Studio reports C4334 "was 64-bit shift intended" warning
because of size mismatch.

Promote unity to the matching type to fit with the `&` operator.

Signed-off-by: Philip Oakley <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: PhilipOakley

builtin/repack.c

@@ -842,7 +842,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
 			fname_old = mkpathdup("%s-%s%s",
 					packtmp, item->string, exts[ext].name);
 
-			if (((uintptr_t)item->util) & (1 << ext)) {
+			if (((uintptr_t)item->util) & ((uintptr_t)1 << ext)) {
 				struct stat statbuffer;
 				if (!stat(fname_old, &statbuffer)) {
 					statbuffer.st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);