scripts: gcc-wrapper: Add exceptions for failures with gcc-4.6.3

Compiling the kernel with gcc-4.6.3 generates two new forbidden
warnings. Adding them to the allowed warnings list.

Warning 1:
kernel/arch/arm/mm/alignment.c:298:15: warning: 'offset.un' may be
used uninitialized in this function [-Wuninitialized]

Warning 2:
kernel/net/sched/sch_generic.c:678:2: warning: the comparison will always
evaluate as 'true' for the address of 'noop_qdisc' will never be NULL
[-Waddress]

Change-Id: Ib559420337ac4c2d25b55eb80e8da3c2221b2f75
Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
(cherry picked from commit 116bcf08bd2c078e809a2d1e53fe901cf6f65502)

Conflicts:

	scripts/gcc-wrapper.py