libitm: Fix privatization safety during upgrades to serial mode.

libitm: Fix privatization safety during upgrades to serial mode.

	libitm/
	* beginend.cc (GTM::gtm_thread::restart): Add and handle
	finish_serial_upgrade parameter.
	* libitm.h (GTM::gtm_thread::restart): Adapt declaration.
	* config/linux/rwlock.cc (GTM::gtm_rwlock::write_lock_generic):
	Don't unset reader flag.
	(GTM::gtm_rwlock::write_upgrade_finish): New.
	* config/posix/rwlock.cc: Same.
	* config/linux/rwlock.h (GTM::gtm_rwlock::write_upgrade_finish):
	Declare.
	* config/posix/rwlock.h: Same.
	* method-serial.cc (GTM::gtm_thread::serialirr_mode): Unset reader
	flag after commit or after rollback when restarting.

From-SVN: r182675