uClibc: fix errno access in pthreads (#8166, #8177) Reading errno within...

uClibc: fix errno access in pthreads (#8166, #8177) Reading errno within pthreads always resulted in 0 breaking various programs like transmission and collectd. This patch is not 100% thread safe but it brings back threading into a usable state for now.

SVN-Revision: 23905