Remove cruft in the default libdvm.so and add 3 more special targets.

Remove cruft in the default libdvm.so and add 3 more special targets.

The idea is similar to having libc.so as the default/optimal build and
libc_debug.so at a handy place.

libdvm.so       : default build to be installed with JIT on and assertion off.
libdvm_interp.so: JIT statically compiled out and assertion off.
libdvm_assert.so: assert/JIT-tuning enabled.
libdvm_sv.so    : assert/JIT-self-verification enabled.

Compile time of "mmm dalvik" from clean build with -j1:

real    2m36.144s
user    2m23.029s
sys     0m12.253s

Compile time of "mmm dalvik" from touching Interp.c with -j1:

real    0m8.493s
user    0m7.416s
sys     0m1.280s

Code size:

638152 Nov  3 16:17 libdvm.so
785604 Nov  3 16:17 libdvm_assert.so
556888 Nov  3 16:17 libdvm_interp.so
793804 Nov  3 16:17 libdvm_sv.so