undefined reference to _nc_mingw_tcgetattr in 6.1 (both unpatched and 20191109)

[Simon Sobisch]

_nc_mingw_tcgetattr is referenced in nc_termios.h and implemented in 
win32con/win_driver.c but I did not spot any object file generation for 
win_driver and no use of it (I *guess* it may is thought to be part of 
libncurses on MinGW).
 
make[1]: Entering directory 
`/tmp/dev/ncurses-snapshots-6_1_20191109/build_msys/progs'
gcc ../objects/tic.o ../objects/dump_entry.o ../objects/tparm_type.o 
../objects/transform.o -L../lib  -DHAVE_CONFIG_H -I../progs -I. -I../../progs 
-I../include -I../../progs/../include -D_XOPEN_SOURCE=600 -DNDEBUG 
-DWINVER=0x0501 -DWIN32_LEAN_AND_MEAN -O2 --param max-inline-insns-single=1200 
-L../lib -static -lncurses -lncurses -dynamic   -lpsapi  -o tic.exe
../lib\libncurses.a(lib_ttyflags.o):lib_ttyflags.c:(.text+0x5d): undefined 
reference to `_nc_mingw_tcgetattr'
../lib\libncurses.a(lib_ttyflags.o):lib_ttyflags.c:(.text+0x111): undefined 
reference to `_nc_mingw_tcsetattr'
collect2.exe: error: ld returned 1 exit status
make[1]: *** [tic.exe] Error 1

I did not test older versions.
Simon