Fix warnings generated by clang 3.0

Fix warnings generated by clang 3.0

Fix warnings like this:

output/outelf32.c:2120:33: warning: equality comparison with extraneous
      parentheses [-Wparentheses-equality]
            if ((match->section == index)) {
                 ~~~~~~~~~~~~~~~^~~~~~~~
output/outelf32.c:2120:33: note: remove extraneous parentheses around the
      comparison to silence this warning
            if ((match->section == index)) {
                ~               ^       ~
output/outelf32.c:2120:33: note: use '=' to turn this equality comparison into
      an assignment
            if ((match->section == index)) {
                                ^~
                                =
1 warning generated.

Signed-off-by: Andrew Nayenko <resver@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>