[patch, testsuite] skip broken test on Windows

[Nick Clifton]

Hi Sandra,

> This patch is a followup to PR23153, in which it was reported that gas's inode comparison test for identical input and output files doesn't work on MinGW hosts, 

Is this still the case ?  We did make some improvements to the code
(So that it also checks the st_dev field, and if the inode is 0,
then the check is assumed to have failed).

Cheers
  Nick