dwarf2ctf: the unit of sou field location is bits [PR101283]

dwarf2ctf: the unit of sou field location is bits [PR101283]

If the value of the DW_AT_data_member_location attribute is constant, the
associated unit is bytes. This patch amends incorrect behaviour which was being
exercised with -gdwarf-2. This caused some of the failures as noted in PR
debug/101283 (specifically the BTF tests involving btm_offset).

The testcase ctf-struct-array-2.c was erroneously checking for the value of
ctm_offset in number of bytes.

The patch fixes the calculation of the field location value for a struct member
in dwarf2ctf and adjusts the testcase. This patch also fixes some of the
failing tests as noted in PR debug/101283.

2021-07-06  Indu Bhagat  <indu.bhagat@oracle.com>

gcc/ChangeLog:

	PR debug/101283
	* dwarf2ctf.c (ctf_get_AT_data_member_location): Multiply by 8 to get
	number of bits.

gcc/testsuite/ChangeLog:

	PR debug/101283
	* gcc.dg/debug/ctf/ctf-struct-array-2.c: Adjust the value in the testcase.