Do not use -pthreads compiler option

Sometimes "-pthreads" is available, sometimes "-pthread" should be
used - and neither can be guaranteed to work.

Apply _THREAD_SAFE for preprocessing and link against pthreads
library instead of using the convenience options.

[Compilation] Do not use -pthreads compiler option. Fixes JB#23605
Merge pull request #15 from spiiroin/jb23605_pthreads_options

Do not use -pthreads compiler option
Bump mce-plugin-libhybris version to 1.4.2