It's really not very hard...
LDFLAGS=-static ./configure --host arm-open2x-linux --without-x --enable-static --disable-shared --enable-lgp2x --disable-modules --prefix=/opt/gp2x --enable-dbglib
This will build static libraries, not shared libraries, in debug and release modes, and link the various programs (demo game, examples, tests) with the release version, totally staticly. Everything gets installed to subdirectories (bin, lib, include, share) of /opt/gp2x.
If you want, you can --enable-dbgprog to build the programs in debug mode too, and link them to the debug library. Up to you.