Description of Problem:
getuid/geteuid don't exist on windows.

Version-Release number of selected component (if applicable):
1.6.4

How Reproducible:
Always.

Steps to Reproduce:
1. CC=i586-mingw32msvc-gcc CXX=i586-mingw32msvc-g++ ./configure --build=i386-linux --host=i586-mingw32msvc
2. make

Actual Results:
/bin/sh ./libtool --mode=link i586-mingw32msvc-gcc  -g -O2  -o test1.exe -all-static test1.o libpopt.la
i586-mingw32msvc-gcc -g -O2 -o test1.exe -static test1.o  ./.libs/libpopt.a
./.libs/libpopt.a(poptconfig.o): In function `poptReadDefaultConfig':
/x/donut/nb/src/popt-1.6.4/poptconfig.c:172: undefined reference to `getuid'
/x/donut/nb/src/popt-1.6.4/poptconfig.c:172: undefined reference to `geteuid'
make[2]: *** [test1.exe] Error 1


Expected Results:
No errors.


Additional Information:
Simple fix, just check for getuid and geteuid in configure.  See attached patch.