cmake: extensions: Remove macro zephyr_library_ifdef.

This cmake macro was changing the control flow of the cmake files.
It is not advisable to modify the callee control flow from inside
a cmake macro.
Hence removing all instances of this macro from the build system.

Fixes: GH-7565

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>