Building with PDF fails

[fhajredini]

make[3]: *** No rule to make target 'PELUX.pdf', needed by 'all-pdf'. Stop.

If you run make sphinx-latexpdf it should build pdf files. Also tested to run cmake -H. -Bbuild -DENABLE_PDF=ON but when ran make still gave the same error.

[sashko]

@fhajredini use internal jira, please.