* include/ruby/defines.h: Simplify the logic to include sys/select.h.
  This fixes a compilation error on Haiku (gcc2 and gcc4).

* configure.in: Use shared linker as $(CC) for Haiku.
  This fixes a build error on Haiku (gcc2).



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40172 b2dd03c8-39d4-4d8f-98ff-823fe69b080e