Bug#903489: warmux FTCBFS: uses AC_RUN_IFELSE

[Helmut Grohne]

Source: warmux
Version: 1:11.04.1+repack2-3
Tags: patch upstream
User: helmutg at debian.org
Usertags: rebootstrap

warmux fails to cross build from source, because it uses AC_RUN_IFELSE
to check the version of SDL_gfx. Unfortunately, AC_RUN_IFELSE cannot be
used for cross compilation at all. Fortunately, the aspectes being
checked are compile time constants, so we can turn it into
AC_COMPILE_IFELSE loosing the printout of the version. Please consider
applying the attached patch as it makes warmux cross buildable. If
printing the version is considered important, one can use AS_COMPUTE_INT
to determine each of the version parts and compose the version in shell.
Let me know if you need that as it is slightly more complex.

Helmut