testsuite, lib: Re-allow mulitple function start labels.

testsuite, lib: Re-allow mulitple function start labels.

The change applied in r14-5760-g2a46e0e7e20 changed the behaviour of
functions with assembly like:

bar:
__acle_se_bar:

Where both bar and __acle_se_bar are globals refering to the same
function body.  The old behaviour overrides 'bar' with '__acle_se_bar'
and the scan tests for that label.

The change here re-allows the override.

Case like this are not legal Mach-O (where two global symbols cannot
have the same address in the assembler output).  However, given the
constraints on the Mach-O scanning, it does not seem that it is
necessary to skip the change (any incorrect case should be easily
evident in the assembler).

gcc/testsuite/ChangeLog:

	* lib/scanasm.exp: Allow multiple function start symbols,
	taking the last as the function name.

Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>