gdb.dwarf2/data-loc.exp: Remove second DW_AT_upper bound in array range.

gdb.dwarf2/data-loc.exp: Remove second DW_AT_upper bound in array range.

The testcase generates an assembly file where a second DW_AT_upper_bound
attribute gets generated in the array range.  This was definitely
unintentional, and I only noticed this after pushing the testcase,
when dumping one more time the DWARF data using readelf.

This patch fixes it.

gdb/testsuite/ChangeLog:

        * gdb.dwarf2/data-loc.exp: Remove second DW_AT_upper bound
        attribute in array range.