x86: Fix off-by-one error in do_elf_reloc_fixups()

The use of post-increment with a do-while loop results in
the loop going one step too far when handling relocation fixups.

In about 1/100 cases this would cause it to hang.
Signed-off-by: NDuncan Laurie <dlaurie@chromium.org>
Signed-off-by: NSimon Glass <sjg@chromium.org>

arch/x86/lib/relocate.c

@@ -85,7 +85,7 @@ int do_elf_reloc_fixups(void)
 				*offset_ptr_ram += gd->reloc_off;
 			}
 		}
-	} while (re_src++ < re_end);
+	} while (++re_src < re_end);
 
 	return 0;
 }