powerpc/spufs: Fix the type of ret in spufs_arch_write_note

Both the ->dump method and snprintf return an int.  So switch to an
int and properly handle errors from ->dump.

Fixes: 5456ffde ("powerpc/spufs: simplify spufs core dumping")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200610085554.5647-1-hch@lst.de

arch/powerpc/platforms/cell/spufs/coredump.c

@@ -118,7 +118,7 @@ static int spufs_arch_write_note(struct spu_context *ctx, int i,
 	size_t sz = spufs_coredump_read[i].size;
 	char fullname[80];
 	struct elf_note en;
-	size_t ret;
+	int ret;
 
 	sprintf(fullname, "SPU/%d/%s", dfd, spufs_coredump_read[i].name);
 	en.n_namesz = strlen(fullname) + 1;