[Ecls-list] Fixed building in Ultrasparc/Solaris

[Juan Jose Garcia-Ripoll]

As mentioned above, ECL now seems to compile on Sun's 64-bit machines. The 
problem was that GMP got compiled using the 64-bit ABI, and ECL used the 
32-bit ABI (the default one).

Side effects: Now the build process uses a first pass of GMP to guess the best 
flags, and later on we configure ECL using these flags. We do so because GMP 
has a wider database of machines, and because it simplifies maintainance of 
ECL.

If you use "--enable-local-gmp" you are responsible for providing a good value 
of CFLAGS and LDFLAGS. This should not be an issue on any platform except 
Solaris/64.

If on Solaris you want to build everything as a 32-bit executable with 32-bit 
pointers, etc. Then do as follows:
	export ABI=32; ./configure

Regards,

Juanjo