LU-969 debug: reduce stack usage

LU-969 debug: reduce stack usage

1, libcfs_debug_vmsg2 to accept libcfs_debug_msg_data struture
   to replace SUBSYSTEM, __FILE__, __FUNCTION__, __LINE__ and
   cdls on the stack

2, CDEBUG, DEBUG_CAPA use static libcfs_debug_msg_data

3, remove the local variable in RETURN/GOTO/__CHECK_STACK

4, reduce stack in recovery thread by moving lu_env,
   ptlrpc_thread to heap.

Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Signed-off-by: Hongchao Zhang <hongchao.zhang@whamcloud.com>
Signed-off-by: Bob Glossman <bogl@whamcloud.com>
Change-Id: I75fe53027f56e27255b5f558e8fd57c7db833648
Reviewed-on: http://review.whamcloud.com/2668
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: Hudson
Reviewed-by: Oleg Drokin <green@whamcloud.com>