The id applet in 1.13.0 only compiles with uclibc < 0.9.30 if the busybox internal passwd/grp functions are used. Therefore, automatically enable CONFIG_USE_BB_PWD_GRP if that situation is detected and warn the user.
busybox 1.13.0 id applet doesn't compile with uclibc 0.9.29 / 0.9.28, so disable it for now.