[binutils-gdb] gdb: Remove unused signal mask

[sergiodj+buildbot at sergiodj dot net]

*** TEST RESULTS FOR COMMIT bf5142e7fef4e2eca5d98cf805dbadc737118c1e ***

Author: Andrew Burgess <andrew.burgess@embecosm.com>
Branch: master
Commit: bf5142e7fef4e2eca5d98cf805dbadc737118c1e

gdb: Remove unused signal mask

In the following commit:

    commit 7feb7d068ae65557ede03c36468ebac61b0939ca
    Date:   Mon May 11 12:08:03 2009 +0000

The last useful uses of normal_mask in linux-nat.c were removed, since
then this variable has sat around being initialised, but never used.
There should be no user visible changes after this commit.

gdb/ChangeLog:

	* linux-nat.c (normal_mask): Delete.
	(_initialize_linux_nat): Don't initialise normal_mask.