Implement the redirector for alpha. Continue to implement more functions

Implement the redirector for alpha. Continue to implement more functions
in jit/jit-rules-alpha.c.

There is enough done on the alpha port to compile the following function
"void func(void) { return; }" and call it 1,000,000 times without anything
crashing. jit_dump_function shows a properly generated prolog and epilog.