mtd: mxc_nand: fix unbalanced enable for IRQ

mtd: mxc_nand: fix unbalanced enable for IRQ

* preset should be done before sending the reset command

* without this, I get the following error on an i.MX35 :
[    0.900000] ------------[ cut here ]------------
[    0.900000] WARNING: at kernel/irq/manage.c:290 __enable_irq+0x4c/0x88()
[    0.900000] Unbalanced enable for IRQ 33
[    0.900000] Modules linked in:
[    0.900000] [<c002ffb8>] (unwind_backtrace+0x0/0xf0) from [<c02f7d0c>] (dump_stack+0x18/0x1c)
[    0.900000] [<c02f7d0c>] (dump_stack+0x18/0x1c) from [<c0049a44>] (warn_slowpath_common+0x54/0x6c)
[    0.900000] [<c0049a44>] (warn_slowpath_common+0x54/0x6c) from [<c0049b00>] (warn_slowpath_fmt+0x38/0x40)
[    0.900000] [<c0049b00>] (warn_slowpath_fmt+0x38/0x40) from [<c008f65c>] (__enable_irq+0x4c/0x88)
[    0.900000] [<c008f65c>] (__enable_irq+0x4c/0x88) from [<c008fca0>] (enable_irq+0x54/0x98)
[    0.900000] [<c008fca0>] (enable_irq+0x54/0x98) from [<c021e618>] (wait_op_done+0x40/0x134)
[    0.900000] [<c021e618>] (wait_op_done+0x40/0x134) from [<c021e808>] (send_cmd+0x30/0x38)
[    0.900000] [<c021e808>] (send_cmd+0x30/0x38) from [<c021eb8c>] (mxc_nand_command+0x26c/0x328)
[    0.900000] [<c021eb8c>] (mxc_nand_command+0x26c/0x328) from [<c021aa60>] (nand_scan_ident+0x188/0x6c0)
[    0.900000] [<c021aa60>] (nand_scan_ident+0x188/0x6c0) from [<c001a9cc>] (mxcnd_probe+0x2b8/0x3d0)
[    0.900000] [<c001a9cc>] (mxcnd_probe+0x2b8/0x3d0) from [<c01f9e88>] (platform_drv_probe+0x20/0x24)
[    0.900000] [<c01f9e88>] (platform_drv_probe+0x20/0x24) from [<c01f8c38>] (driver_probe_device+0xb0/0x164)
[    0.900000] [<c01f8c38>] (driver_probe_device+0xb0/0x164) from [<c01f8d54>] (__driver_attach+0x68/0x8c)
[    0.900000] [<c01f8d54>] (__driver_attach+0x68/0x8c) from [<c01f8348>] (bus_for_each_dev+0x50/0x84)
[    0.900000] [<c01f8348>] (bus_for_each_dev+0x50/0x84) from [<c01f8a9c>] (driver_attach+0x20/0x28)
[    0.900000] [<c01f8a9c>] (driver_attach+0x20/0x28) from [<c01f7c00>] (bus_add_driver+0x144/0x2dc)
[    0.900000] [<c01f7c00>] (bus_add_driver+0x144/0x2dc) from [<c01f906c>] (driver_register+0xb0/0x13c)
[    0.900000] [<c01f906c>] (driver_register+0xb0/0x13c) from [<c01fa13c>] (platform_driver_register+0x4c/0x60)
[    0.900000] [<c01fa13c>] (platform_driver_register+0x4c/0x60) from [<c01fa170>] (platform_driver_probe+0x20/0xa0)
[    0.900000] [<c01fa170>] (platform_driver_probe+0x20/0xa0) from [<c001a708>] (mxc_nd_init+0x18/0x24)
[    0.900000] [<c001a708>] (mxc_nd_init+0x18/0x24) from [<c002938c>] (do_one_initcall+0x64/0x1bc)
[    0.900000] [<c002938c>] (do_one_initcall+0x64/0x1bc) from [<c00084c4>] (kernel_init+0xe8/0x1ac)
[    0.900000] [<c00084c4>] (kernel_init+0xe8/0x1ac) from [<c002aee8>] (kernel_thread_exit+0x0/0x8)
[    0.900000] ---[ end trace 8bf72ac6ba089a19 ]---
[    1.140000] NAND device: Manufacturer ID: 0x2c, Chip ID: 0xda (Micron NAND 256MiB 3,3V 8-bit)

Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>