bzip2: code shrink

bzip2: code shrink

function                                             old     new   delta
bsW16                                                  -      59     +59
sendMTFValues                                       2116    2111      -5
bsPutU16                                              36       -     -36
bsPutU32                                              76      31     -45
------------------------------------------------------------------------------
(add/remove: 1/1 grow/shrink: 0/2 up/down: 59/-86)            Total: -27 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>