The lcdc device is missing the dma_coherent_mask definition causing the
following warning on da850-evm:

da8xx_lcdc da8xx_lcdc.0: found Sharp_LK043T1DG01 panel
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at kernel/dma/mapping.c:247 dma_alloc_attrs+0xc8/0x110
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 5.2.0-rc3-00077-g16d72dd4 #18
Hardware name: DaVinci DA850/OMAP-L138/AM18x EVM
[<c000fce8>] (unwind_backtrace) from [<c000d900>] (show_stack+0x10/0x14)
[<c000d900>] (show_stack) from [<c001a4f8>] (__warn+0xec/0x114)
[<c001a4f8>] (__warn) from [<c001a634>] (warn_slowpath_null+0x3c/0x48)
[<c001a634>] (warn_slowpath_null) from [<c0065860>] (dma_alloc_attrs+0xc8/0x110)
[<c0065860>] (dma_alloc_attrs) from [<c02820f8>] (fb_probe+0x228/0x5a8)
[<c02820f8>] (fb_probe) from [<c02d3e9c>] (platform_drv_probe+0x48/0x9c)
[<c02d3e9c>] (platform_drv_probe) from [<c02d221c>] (really_probe+0x1d8/0x2d4)
[<c02d221c>] (really_probe) from [<c02d2474>] (driver_probe_device+0x5c/0x168)
[<c02d2474>] (driver_probe_device) from [<c02d2728>] (device_driver_attach+0x58/0x60)
[<c02d2728>] (device_driver_attach) from [<c02d27b0>] (__driver_attach+0x80/0xbc)
[<c02d27b0>] (__driver_attach) from [<c02d047c>] (bus_for_each_dev+0x64/0xb4)
[<c02d047c>] (bus_for_each_dev) from [<c02d1590>] (bus_add_driver+0xe4/0x1d8)
[<c02d1590>] (bus_add_driver) from [<c02d301c>] (driver_register+0x78/0x10c)
[<c02d301c>] (driver_register) from [<c000a5c0>] (do_one_initcall+0x48/0x1bc)
[<c000a5c0>] (do_one_initcall) from [<c05cae6c>] (kernel_init_freeable+0x10c/0x1d8)
[<c05cae6c>] (kernel_init_freeable) from [<c048a000>] (kernel_init+0x8/0xf4)
[<c048a000>] (kernel_init) from [<c00090e0>] (ret_from_fork+0x14/0x34)
Exception stack(0xc6837fb0 to 0xc6837ff8)
7fa0:                                     00000000 00000000 00000000 00000000
7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
---[ end trace 8a8073511be81dd2 ]---

Add a 32-bit mask to the platform device's definition.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>