[Xotcl] nx: make failing on strnstr()

[Victor Mayevski]

Hello Gustaf,

./generic/nsf.c: In function ‘ParamOptionParse’:
./generic/nsf.c:8281: warning: implicit declaration of function ‘strnstr’
./generic/nsf.c:8281: warning: assignment makes pointer from integer
without a cast
./generic/nsf.c: At top level:
./generic/nsfStack.c:1015: warning: ‘BeginOfCallChain’ defined but not used

It seems that strnstr() function is new to Linux (as of January 2010)
and is not present in many Linux libraries yet. May be you can
substitute it with something else.