[MPlayer-dev-eng] Remove internal mp3lib forked copy

[Ivan Kalvachev]

A little bit off-topic.

with mpg123 in very rare cases, mostly after seeking, I get something like:

A:   0.2 V:   0.0 A-V:  0.183 ct: -0.011   1/  1 ??% ??% ??,?% 0 0 84%
mpg123 failed to reopen stream: Error reading the stream. (code 18)
mpg123 cannot reopen stream for resync.
mpg123 decoding failed: No stream opened. (code 24)
A:  60.2 V:  60.2 A-V:  0.014 ct:  0.001 1804/1804 ??% ??% ??,?% 0 0 65%
mpg123 decoding failed: No stream opened. (code 24)

It goes on like this until I seek again.
Can you do something to make the resync a little bit more resilient.