arc: Use correct string when printing bfd DEBUG data

PRINT_DEBUG_RELOC_INFO_BEFORE() macro prints bunch of parameters
for debugging purposes.  Due to a seemingly copy/paste mistake,
the "input_section->vma" is printed under the field name
"symbol_section->vma".  This commit fixes that.

This fix is a courtesy of xiangzhai.

	* elf32-arc.c (PRINT_DEBUG_RELOC_INFO_BEFORE): Use the
	correct field name in the output string.