patch 8.1.0377: xdiff doesn't use the Vim memory allocation functions

Problem:    Xdiff doesn't use the Vim memory allocation functions.
Solution:   Change the xdl_ defines.  Check for out-of-memory.  Rename
            "ignored" to "vim_ignored".
diff --git a/src/xdiff/xdiff.h b/src/xdiff/xdiff.h
index 2356da5..476b20c 100644
--- a/src/xdiff/xdiff.h
+++ b/src/xdiff/xdiff.h
@@ -108,10 +108,11 @@
 	long bsize;
 } bdiffparam_t;
 
+#include "vim.h"
 
-#define xdl_malloc(x) malloc(x)
-#define xdl_free(ptr) free(ptr)
-#define xdl_realloc(ptr,x) realloc(ptr,x)
+#define xdl_malloc(x) lalloc((x), TRUE)
+#define xdl_free(ptr) vim_free(ptr)
+#define xdl_realloc(ptr,x) vim_realloc((ptr),(x))
 
 void *xdl_mmfile_first(mmfile_t *mmf, long *size);
 long xdl_mmfile_size(mmfile_t *mmf);