[7.7.1] Blocker patch (GCC 4.9 compat)

[Sergio Durigan Junior <sergiodj@redhat.com>]

Hi Joel,

I tested the GDB 7.7 branch using GCC 4.9 to build it, and found some
errors.

  In file included from ../../gdb/defs.h:104:0,
                   from ../../gdb/cli/cli-dump.c:22:
  ../../gdb/cli/cli-dump.c: In function 'dump_bfd_file':
  ../bfd/bfd.h:302:108: error: right-hand operand of comma expression has no effect [-Werror=unused-value]
   #define bfd_set_section_vma(bfd, ptr, val) (((ptr)->vma = (ptr)->lma = (val)), ((ptr)->user_set_vma = TRUE), TRUE)
                                                                                                              ^
  ../../gdb/cli/cli-dump.c:197:3: note: in expansion of macro 'bfd_set_section_vma'
     bfd_set_section_vma (obfd, osection, vaddr);
     ^
  ../bfd/bfd.h:303:83: error: right-hand operand of comma expression has no effect [-Werror=unused-value]
   #define bfd_set_section_alignment(bfd, ptr, val) (((ptr)->alignment_power = (val)),TRUE)
                                                                                     ^
  ../../gdb/cli/cli-dump.c:198:3: note: in expansion of macro 'bfd_set_section_alignment'
     bfd_set_section_alignment (obfd, osection, 0);

They have been fixed by the following commit:

  commit 27b829ee701e29804216b3803fbaeb629be27491
  Author: Nick Clifton <nickc@redhat.com>
  Date:   Wed Jan 29 13:46:39 2014 +0000

So I am proposing that we backport this commit to the 7.7 branch.  I can
do that if it is OK.

WDYT?  Thanks,

-- 
Sergio