[gpm] [Patch] Fix a slight segfault in the code to stop the critical alarm loop

[Pramod Dematagoda <pmd lotr gandalf gmail com>]

Hey Richard,

I discovered a tiny memory fault in the code that deals with removing
the current critical alarm loop via valgrind, so I'm sending a patch
that fixes it and simplifies the code a bit too. Also I found a trivial
error in the previously sent code too, so I attached the patch to fix
that too. My apologies for the errors. :)

Cheers,
Pramod