clockfix: Do not use __GNUC_PREREQ macro because it may not exist.

git-svn-id: http://streamboard.de.vu/svn/oscam/trunk@9284 4b0bc96b-bc66-0410-9d44-ebda105a78c1
clockfix: Fix build on Android.

Android's libc in NDK r9c do not ship with -lrt and pthread_condattr_setclock().

git-svn-id: http://streamboard.de.vu/svn/oscam/trunk@9285 4b0bc96b-bc66-0410-9d44-ebda105a78c1