Correct layout of RT2661_TXRX_CSR4

Correct layout of RT2661_TXRX_CSR4

Obtained-from: Linux RT61 driver

#
# Result of:
# ping -c 100 -i 0.1 -s 1300 192.168.3.2
#
# Before this commit
# --- 192.168.3.2 ping statistics ---
# 100 packets transmitted, 37 packets received, 63% packet loss
# round-trip min/avg/max/stddev = 1.578/1.844/3.113/0.310 ms
#
# After this commit
# --- 192.168.3.2 ping statistics ---
# 100 packets transmitted, 100 packets received, 0% packet loss
# round-trip min/avg/max/stddev = 2.043/2.894/4.514/0.529 ms
#
# Maybe "63% packet loss" should be taken as "this card works well" :-P
#