Remove Fuchsia-specific fstat workaround

fstat() now works properly on pipe files, so we don't need to work
around this check.

Change-Id: I1c73c730e835217c3d1e90a1b8c3ee0fe1d38713
diff --git a/builtin/index-pack.c b/builtin/index-pack.c
index 04d52ec..f4b87c6 100644
--- a/builtin/index-pack.c
+++ b/builtin/index-pack.c
@@ -1158,15 +1158,11 @@
 	use(20);
 
 	/* If input_fd is a file, we should have reached its end now. */
-#ifndef __Fuchsia__ // TODO: fstat(0, ...) seems to fail, oddly
 	if (fstat(input_fd, &st))
 		die_errno(_("cannot fstat packfile"));
 	if (S_ISREG(st.st_mode) &&
 			lseek(input_fd, 0, SEEK_CUR) - input_len != st.st_size)
 		die(_("pack has junk at the end"));
-#else
-    (void)st;
-#endif
 
 	for (i = 0; i < nr_objects; i++) {
 		struct object_entry *obj = &objects[i];