net: usb: modify rx_urb_size size for dm9601

net: usb: modify rx_urb_size size for dm9601

fix error:
[  103.825058] DWC_OTG Transfer buffer length less than actual buffer lengthactual_length 1536 , buffer_length 1522 urb->complete rx_complete+0x0/0x1cc
[  103.839742] skbuff: skb_over_panic: text:ffffff80086e1f74 len:1536 put:1536 head:ffffffc06118da80 data:ffffffc06118dac2 tail:0x642 end:0x640 dev:eth0
[  103.839960] ------------[ cut here ]------------
[  103.839989] kernel BUG at net/core/skbuff.c:104!
[  103.840027] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[  104.008320] read channel() error: -110
[  104.218321] read channel() error: -110
[  104.428304] read channel() error: -110
[  104.638314] read channel() error: -110
[  104.848296] read channel() error: -110
[  105.058314] read channel() error: -110
[  105.268303] read channel() error: -110
[  105.280141] Modules linked in: pvrsrvkm(O)
[  105.284297] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W  O    4.4.66 #26
[  105.291524] Hardware name: Rockchip rk3368 p9 board (DT)
[  105.296850] task: ffffff8009165090 ti: ffffff8009150000 task.ti: ffffff8009150000
[  105.304352] PC is at skb_panic+0x4c/0x50
[  105.308290] LR is at skb_panic+0x4c/0x50
[  105.312227] pc : [<ffffff80089436f8>] lr : [<ffffff80089436f8>] pstate: 604001c5
[  105.319624] sp : ffffffc07db5b890
[  105.322948] x29: ffffffc07db5b8a0 x28: 0000000000000002
[  105.328296] x27: ffffff80095805ec x26: ffffff80095805e8
[  105.333643] x25: 0000000000000002 x24: 0000000000000002
[  105.338988] x23: ffffff80095805e0 x22: ffffffc06114fb00
[  105.344335] x21: 0000000000000000 x20: ffffffc047837b40
[  105.349683] x19: ffffffc0793ac800 x18: 0000000000000000
[  105.355029] x17: 00000078da08d124 x16: ffffff80081f1438
[  105.360376] x15: 000000000000000c x14: 636666666666663a
[  105.365723] x13: 6461656820363335 x12: 313a747570203633
[  105.371071] x11: 35313a6e656c2034 x10: 3766316536383030
[  105.376417] x9 : 386666666666663a x8 : 303a646e65203234
[  105.381764] x7 : 000000000000000a x6 : 000000000000000d
[  105.387110] x5 : 0000000000000001 x4 : 0000000000000001
[  105.392455] x3 : 0000000000000007 x2 : cb88537fdc8ba642
[  105.397802] x1 : cb88537fdc8ba642 x0 : 0000000000000089

Change-Id: Ie11f20d62bec7d0d35b82d0bb5535d3c8d9213b9
Signed-off-by: zzc <zzc@rock-chips.com>