Bitfield Clear sets a bitfield of <width> bits at bit position <lsb> of the destination register to zero, leaving the other destination bits unchanged.
位域清除将目标寄存器位位置<lsb>处<width>位的位域设置为零，而保留其他目标位不变。
32-bit variant
Applies when sf == 0 && N == 0.
BFC <Wd>, #<lsb>, #<width>
64-bit variant
Applies when sf == 1 && N == 1.
BFC <Xd>, #<lsb>, #<width>
