Reliant UNIX configuration problems

[John Carr]

SINIX was renamed Reliant UNIX recently.

1. config.guess fails on Reliant UNIX 5.44

On this system, 

	uname -m matches RM*
	uname -r is 5.44
	uname -s matches ReliantUNIX-*
	uname -v is unimportant

5.44 adds 64 bit support so it should probably have a different configure
name than 5.43.  The assembler also seems to act differently; I'm still
investigating that.

2. Given target alias mips-sni-sysv4, configure guesses the correct
compiler (cc) but the x-sni-svr4 file overrides it to set
CC=cc -Olimit 3000.  The 5.44 compiler (CDS++) does not support -Olimit.


The behavior is the same on the development and 1.1 branches.