Patch:RFA:sim testsuite: Options Embedded in Test Cases

[Dave Brolley]

Hi,

The attached patch addresses two issues:

1) Yet another attempt at passing the correct cpu to the assembler
when more than one machine is being tested. This time I've defined a
global variable 'cpu_option' which the caller can set to indicate the
name of the option which specifies the cpu.

2) Resetting options between test cases. Currently options from
previous test cases are not cleared and sometimes they leak into
subsequent tests. Specifically unsetting them seems to be the only way
to make the "if [info exists <option>]" tests work properly.

Tested against m32r (which does not specify 'cpu_option', but has more
than one machine) and two internal ports (one of which uses
'cpu_option' and has mutiple machines to test).

OK to commit?

Dave