var.c: 1.44->1.45

var.c: 1.44->1.45
Author: ru
Log:
Moved the code for :U and :L modifiers where it belongs, so that
the fallback for SysV (now in POSIX) variable substitution works
for old_string arguments starting with 'U' or 'L'.

var.c:1.45->1.46
Author: harti
Log:
Allow variable substitutions in SYSV variable substitutions like
$(SRC:.c=$O). This brings us closer to other makes.

Reviewed by:    ru
Obtained from:  NetBSD

Obtained-from: FreeBSD
Submitted-by: Max Okumoto <okumoto@ucsd.edu>