Log Message:
ast-ksh: fix compilation on NetBSD, possibly linux too.

Fix "storage size of buf is not known" likely caused by it being defined
to be something with sizeof().
add LDFLAGS -lm to all operating systems (I see undefined reference to
frexpl/ldexpl), remove duplicate from other operating systems.

bump PKGREVISION sinze L_tmpnam will be changed for the few who can build
the package.