[coreboot] msrtool: posix-ify configure script

[Peter Stuge]

Andriy Gapon wrote:
> 
> Please review the following patch.
> It changes a few bash-specific constructs to more portable syntax specified by
> POSIX.  After the change the script keeps working with bash interpreter and can
> also be interpreted by FreeBSD /bin/sh.
> 
> Signed-off-by:	Andriy Gapon <avg at icyb.net.ua>

Acked-by: Peter Stuge <peter at stuge.se>

I rebased the patch to current trunk and committed as r4964.


//Peter