Several kf5 qt5 ports fail build

[Per olof Ljungmark]

Updated ports and 12.1-STABLE r362185

Failures like this, anyone here having the same problem or am I alone?

Determining if the __GLIBC__ exist failed with the following output:
Change Dir: 
/usr/ports/x11-toolkits/kf5-kdesignerplugin/work/.build/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/local/bin/ninja cmTC_8b830 && [1/2] Building C 
object CMakeFiles/cmTC_8b830.dir/CheckSymbolExists.c.o
FAILED: CMakeFiles/cmTC_8b830.dir/CheckSymbolExists.c.o
/usr/bin/cc   -O2 -pipe  -fstack-protector-strong -fno-strict-aliasing 
-o CMakeFiles/cmTC_8b830.dir/CheckSymbolExists.c.o   -c CheckSymbolExists.c
CheckSymbolExists.c:8:19: error: use of undeclared identifier '__GLIBC__'
   return ((int*)(&__GLIBC__))[argc];
                   ^
1 error generated.
ninja: build stopped: subcommand failed.


File 
/usr/ports/x11-toolkits/kf5-kdesignerplugin/work/.build/CMakeFiles/CMakeTmp/CheckSymbolExists.c:
/* */
#include <stdlib.h>

int main(int argc, char** argv)
{
   (void)argv;
#ifndef __GLIBC__
   return ((int*)(&__GLIBC__))[argc];
#else
   (void)argc;
   return 0;
#endif
}