LD: Fix .startof.SECNAME/.sizeof.SECNAME tests for MIPS/IRIX

LD: Fix .startof.SECNAME/.sizeof.SECNAME tests for MIPS/IRIX

Correct .startof.SECNAME/.sizeof.SECNAME tests for MIPS/IRIX targets,
complementing commit dc74becf498f ("ld: Add tests for -Ur") and commit
da614360f520 ("ld: Add tests for .startof.SECNAME/.sizeof.SECNAME") with
subsequent updates, and in reference to commit cbd0eecf261c ("Always
define referenced __start_SECNAME/__stop_SECNAME") and commit
7dba9362c172 ("Rewrite __start and __stop symbol handling").

These targets set the STT_OBJECT type for non-function symbol
references, according to `elf_frob_symbol' code in gas/config/obj-elf.c:

  /* The Irix 5 and 6 assemblers set the type of any common symbol and
     any undefined non-function symbol to STT_OBJECT.  We try to be
     compatible, since newer Irix 5 and 6 linkers care.  However, we
     only set undefined symbols to be STT_OBJECT if we are on Irix,
     because that is the only time gcc will generate the necessary
     .global directives to mark functions.  */

  if (S_IS_COMMON (symp))
    symbol_get_bfdsym (symp)->flags |= BSF_OBJECT;

  if (strstr (TARGET_OS, "irix") != NULL
      && ! S_IS_DEFINED (symp)
      && (symbol_get_bfdsym (symp)->flags & BSF_FUNCTION) == 0)
    symbol_get_bfdsym (symp)->flags |= BSF_OBJECT;

and consequently entries in the symbol table listing from `readelf'
produced with these tests do not match the NOTYPE pattern expected,
causing test suite failures:

FAIL: ld-elf/sizeofa
FAIL: ld-elf/sizeofc
FAIL: ld-elf/startofa
FAIL: ld-elf/startofc

specifically with the `mips-sgi-irix5' and `mips-sgi-irix6' targets.

Given that it does not matter for the feature covered by these tests
whether the type of the symbols produced is STT_NOTYPE or STT_OBJECT
adjust the problematic cases to accept either type, removing the
failures observed.

	ld/
	* testsuite/ld-elf/sizeofa.d: Also accept the OBJECT type for
	the symbols examined.
	* testsuite/ld-elf/sizeofc.d: Likewise.
	* testsuite/ld-elf/startofa.d: Likewise.
	* testsuite/ld-elf/startofc.d: Likewise.