readelf: replace xmalloc with malloc in slurp_relr_relocs

Using xmalloc makes the null check redundant since failing allocation
will exit the program. Instead use malloc and let the error be
conveyed up the call chain.

binutils/readelf.c

@@ -1401,7 +1401,7 @@ slurp_relr_relocs (Filedata * filedata,
 	    size++;
     }
 
-  *relrsp = (bfd_vma *) xmalloc (size * sizeof (bfd_vma));
+  *relrsp = (bfd_vma *) malloc (size * sizeof (bfd_vma));
   if (*relrsp == NULL)
     {
       free (relrs);