gst1-plugins-bad: remove obsolete make rules

Commit 83e29f26 "gst1-plugins-bad: bump
version" (from 1.2.4 to 1.4.1) removed the configuration options for the
cdaudio and eglglessink plugins as a consequence of their removal in
1.3.1. However, that commit did not remove the corresponding make rules,
so remove them now.

Signed-off-by: Benoît Thébaudeau <benoit@wsystem.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>