gpu: arm: mali400: fix warning on booting

gpu: arm: mali400: fix warning on booting

This fixes below warnings.

[    1.461424] ------------[ cut here ]------------
[    1.464524] WARNING: at fs/proc/generic.c:101 __xlate_proc_name+0xa8/0xbc()
[    1.471444] name '/gpu@13000000'
[    1.474651] Modules linked in:
[    1.477678] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.39-01649-g6491ddb-dirty #15
[    1.485623] [<c0014224>] (unwind_backtrace+0x0/0xf4) from [<c0011520>] (show_stack+0x10/0x14)
[    1.494120] [<c0011520>] (show_stack+0x10/0x14) from [<c001ff7c>] (warn_slowpath_common+0x54/0x6c)
[    1.503050] [<c001ff7c>] (warn_slowpath_common+0x54/0x6c) from [<c001ffc4>] (warn_slowpath_fmt+0x30/0x40)
[    1.512598] [<c001ffc4>] (warn_slowpath_fmt+0x30/0x40) from [<c010774c>] (__xlate_proc_name+0xa8/0xbc)
[    1.521886] [<c010774c>] (__xlate_proc_name+0xa8/0xbc) from [<c01077ac>] (__proc_create+0x4c/0x100)
[    1.530910] [<c01077ac>] (__proc_create+0x4c/0x100) from [<c0107b18>] (proc_mkdir_data+0x2c/0x68)
[    1.539766] [<c0107b18>] (proc_mkdir_data+0x2c/0x68) from [<c007b72c>] (register_handler_proc+0xd8/0xf0)
[    1.549233] [<c007b72c>] (register_handler_proc+0xd8/0xf0) from [<c0077b38>] (__setup_irq+0x1e4/0x440)
[    1.558525] [<c0077b38>] (__setup_irq+0x1e4/0x440) from [<c0077ec4>] (request_threaded_irq+0xa8/0x128)
[    1.567817] [<c0077ec4>] (request_threaded_irq+0xa8/0x128) from [<c02a6f34>] (_mali_osk_irq_init+0x64/0x124)
[    1.577628] [<c02a6f34>] (_mali_osk_irq_init+0x64/0x124) from [<c02afa58>] (mali_pp_create+0xac/0x23c)
[    1.586899] [<c02afa58>] (mali_pp_create+0xac/0x23c) from [<c02aa94c>] (mali_initialize_subsystems+0x21c/0x7d8)
[    1.596966] [<c02aa94c>] (mali_initialize_subsystems+0x21c/0x7d8) from [<c02ab854>] (mali_probe+0x3c/0x254)
[    1.606697] [<c02ab854>] (mali_probe+0x3c/0x254) from [<c02bd314>] (driver_probe_device+0x88/0x244)
[    1.615715] [<c02bd314>] (driver_probe_device+0x88/0x244) from [<c02bd5a0>] (__driver_attach+0x8c/0x90)
[    1.625089] [<c02bd5a0>] (__driver_attach+0x8c/0x90) from [<c02bb8f0>] (bus_for_each_dev+0x60/0x94)
[    1.634121] [<c02bb8f0>] (bus_for_each_dev+0x60/0x94) from [<c02bcb68>] (bus_add_driver+0x1c0/0x24c)
[    1.643232] [<c02bcb68>] (bus_add_driver+0x1c0/0x24c) from [<c02bdb78>] (driver_register+0x78/0x140)
[    1.652345] [<c02bdb78>] (driver_register+0x78/0x140) from [<c02abaa4>] (mali_module_init+0xc/0x50)
[    1.661370] [<c02abaa4>] (mali_module_init+0xc/0x50) from [<c000870c>] (do_one_initcall+0x108/0x158)
[    1.670505] [<c000870c>] (do_one_initcall+0x108/0x158) from [<c07bec54>] (kernel_init_freeable+0x13c/0x1dc)
[    1.680214] [<c07bec54>] (kernel_init_freeable+0x13c/0x1dc) from [<c05a05bc>] (kernel_init+0xc/0x160)
[    1.689411] [<c05a05bc>] (kernel_init+0xc/0x160) from [<c000df58>] (ret_from_fork+0x14/0x3c)
[    1.697837] ---[ end trace e694d4bb842a349f ]---

Change-Id: Ic2b9ef0388f929e5d028ccd3b10882aecc9c815e
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>