Add support for the separate tinfo library from ncurses

Build ifpps and flowtop failed
```
/usr/lib64/gcc/x86_64-slackware-linux/4.8.2/../../../../x86_64-slackware-linux/bin/ld: flowtop/screen.o: undefined reference to symbol 'cbreak'
/usr/lib64/gcc/x86_64-slackware-linux/4.8.2/../../../../x86_64-slackware-linux/bin/ld: note: 'cbreak' is defined in DSO /usr/lib64/libtinfo.so.5 so try adding it to the linker command line
/usr/lib64/libtinfo.so.5: could not read symbols: Invalid operation
collect2: error: ld returned 1 exit status
```
caused by missing tinfo LDFLAGS
```
/usr/lib64/gcc/x86_64-slackware-linux/4.8.2/../../../../x86_64-slackware-linux/bin/ld: ifpps/screen.o: undefined reference to symbol 'cbreak'
/usr/lib64/gcc/x86_64-slackware-linux/4.8.2/../../../../x86_64-slackware-linux/bin/ld: note: 'cbreak' is defined in DSO /usr/lib64/libtinfo.so.5 so try adding it to the linker command line
/usr/lib64/libtinfo.so.5: could not read symbols: Invalid operation
collect2: error: ld returned 1 exit status
```