LU-6916 target: fix ted_lcd_lock init

LU-6916 target: fix ted_lcd_lock init

Move ted_lcd_lock init from tgt_client_new()
to tgt_client_alloc(), otherwise if error happens
in client_new_export(), the error handler path
will cause panic like this

<1>BUG: unable to handle kernel NULL pointer dereference at (null)
<1>IP: [<ffffffff812957f6>] __list_add+0x26/0xa0
<4> [<ffffffff8152adef>] __mutex_lock_slowpath+0xcf/0x180
<4> [<ffffffffa047e087>] ? cfs_hash_putref+0x2e7/0x480 [libcfs]
<4> [<ffffffff8152acfb>] mutex_lock+0x2b/0x50
<4> [<ffffffffa083db72>] tgt_client_free+0x62/0x610 [ptlrpc]
<4> [<ffffffffa0f59f84>] mdt_destroy_export+0x74/0x220 [mdt]
<4> [<ffffffffa05862c5>] class_new_export+0x315/0x9c0 [obdclass]
<4> [<ffffffffa058745e>] class_connect+0xae/0x250 [obdclass]
<4> [<ffffffffa0f57fd1>] mdt_obd_connect+0xb1/0x720 [mdt]
<4> [<ffffffffa07aaf78>] target_handle_connect+0xe58/0x2d30 [ptlrpc]
<4> [<ffffffff8128c1f0>] ? string+0x40/0x100
<4> [<ffffffffa084edf2>] tgt_request_handle+0x5b2/0x1230 [ptlrpc]
<4> [<ffffffffa07f7611>] ptlrpc_main+0xe41/0x1920 [ptlrpc]
<4> [<ffffffffa07f67d0>] ? ptlrpc_main+0x0/0x1920 [ptlrpc]
<4> [<ffffffff8109abf6>] kthread+0x96/0xa0
<4> [<ffffffff8100c20a>] child_rip+0xa/0x20
<4> [<ffffffff8109ab60>] ? kthread+0x0/0xa0
<4> [<ffffffff8100c200>] ? child_rip+0x0/0x20

Signed-off-by: wang di <di.wang@intel.com>
Change-Id: If09c019384f53a63107aeaa293ef93d6415f81b5
Reviewed-on: http://review.whamcloud.com/15770
Tested-by: Jenkins
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>