MLK-11392-1 ASoC: fsl_sai: Move pm runtime enable/disable out trigger function

When building kernel with CONFIG_DEBUG_ATOMIC_SLEEP=y, there will be
kernel dump.

BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:954
in_atomic(): 1, irqs_disabled(): 128, pid: 705, name: aplay
CPU: 0 PID: 705 Comm: aplay Not tainted 3.10.53-02755-gbee6071 #1472
[<80013f4c>] (unwind_backtrace+0x0/0xf8) from [<800119c0>] (show_stack+0x10/0x14)
[<800119c0>] (show_stack+0x10/0x14) from [<8031fd68>] (__pm_runtime_resume+0x88/0x90)
[<8031fd68>] (__pm_runtime_resume+0x88/0x90) from [<80509ba8>] (fsl_sai_trigger+0x98/0x300)
[<80509ba8>] (fsl_sai_trigger+0x98/0x300) from [<804fef9c>] (soc_pcm_trigger+0x90/0xa0)
[<804fef9c>] (soc_pcm_trigger+0x90/0xa0) from [<804eae60>] (snd_pcm_do_start+0x2c/0x30)
[<804eae60>] (snd_pcm_do_start+0x2c/0x30) from [<804eaad8>] (snd_pcm_action_single+0x38/0x78)
[<804eaad8>] (snd_pcm_action_single+0x38/0x78) from [<804eada8>] (snd_pcm_action_lock_irq+0x84/0xa4)
[<804eada8>] (snd_pcm_action_lock_irq+0x84/0xa4) from [<804eba58>] (snd_pcm_common_ioctl1+0x16c/0xd68)
[<804eba58>] (snd_pcm_common_ioctl1+0x16c/0xd68) from [<804ecc8c>] (snd_pcm_playback_ioctl1+0x158/0x4d0)
[<804ecc8c>] (snd_pcm_playback_ioctl1+0x158/0x4d0) from [<800d5bb8>] (do_vfs_ioctl+0x80/0x624)
[<800d5bb8>] (do_vfs_ioctl+0x80/0x624) from [<800d6198>] (SyS_ioctl+0x3c/0x5c)
[<800d6198>] (SyS_ioctl+0x3c/0x5c) from [<8000e200>] (ret_fast_syscall+0x0/0x30)

Signed-off-by: Shengjiu Wang <shengjiu.wang@freescale.com>
(cherry picked from commit 99095f3362bc53eb414dabbbe7da5778f3d54f25)