gcc.misc-tests/outputs.exp: enumerate tests

gcc.misc-tests/outputs.exp: enumerate tests

Go from:
PASS: outputs asm default 1: outputs-0.s
PASS: outputs asm default 1: extra
PASS: outputs asm default 1: std out
PASS: outputs asm default 2: outputs-1.s
PASS: outputs asm default 2: outputs-2.s
PASS: outputs asm default 2: extra
PASS: outputs asm default 2: std out
PASS: outputs obj default 1: outputs-0.o
PASS: outputs obj default 1: extra
PASS: outputs obj default 1: std out
...

to:
PASS: outputs-1 asm default 1: outputs-0.s
PASS: outputs-1 asm default 1: extra
PASS: outputs-1 asm default 1: std out
PASS: outputs-2 asm default 2: outputs-1.s
PASS: outputs-2 asm default 2: outputs-2.s
PASS: outputs-2 asm default 2: extra
PASS: outputs-2 asm default 2: std out
PASS: outputs-3 obj default 1: outputs-0.o
PASS: outputs-3 obj default 1: extra
PASS: outputs-3 obj default 1: std out
...

thereby helping a human to quickly pin-point the result of a
specific test.

This mechanical patch was produced by applying
perl -pe 's/^(outest "\$b) /sprintf("%s-%d ",$1, ++$n)/e;'
to outputs.exp.

gcc/testsuite:
	* gcc.misc-tests/outputs.exp: Enumerate tests.