Un-XFAIL 'dg-note's in 'gfortran.dg/goacc/routine-external-level-of-parallelism-2.f'

As of the recent commit 65286465
"Fortran: Fix location_t in gfc_get_extern_function_decl; [...]" change:

    The declaration created by gfc_get_extern_function_decl used input_location
    as DECL_SOURCE_LOCATION, which gave rather odd results with 'declared here'
    diagnostic. - It is much more useful to use the gfc_symbol's declated_at,
    which this commit now does.

..., we're no longer using the 'dg-bogus' location informations, as pointed out
for one class of additional notes of
'gfortran.dg/goacc/routine-external-level-of-parallelism-2.f', once added in
commit 03eb7791 "Add 'dg-note', 'dg-lto-note'".
Therefore, un-XFAILed 'dg-note's rather than XFAILed 'dg-bogus'es.

	gcc/testsuite/
	* gfortran.dg/goacc/routine-external-level-of-parallelism-2.f:
	Un-XFAIL 'dg-note's.