package/omniorb: bump version to 4.2.1

package/omniorb: bump version to 4.2.1

Removed patch applied upstream:
https://sourceforge.net/p/omniorb/svn/6296/#diff-4

Please note that upstream also provides version 4.2.1-2
https://sourceforge.net/projects/omniorb/files/omniORB/omniORB-4.2.1/

This version was a follow-up to 4.2.1 to provide VS platform files:
https://sourceforge.net/p/omniorb/svn/6311/#diff-5
https://sourceforge.net/p/omniorb/svn/6313/#diff-2

Because they are not needed for buildroot we stick to version 4.2.1.

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>