Revert "avcodec/options_table: set err_detect to careful by default"

This reverts commit b1348eb68b432041b2557b9073590cf0fa60ff14.
Revert "avcodec/options_table: disable CRC checking by default"

This reverts commit c7027ce9eac04fb20bd85fa37dbf24856c080c45.

It appears there is no complete consensus on this currently.
avcodec/hevc: calculate checksum only if AV_EF_EXPLODE is set

This avoids a slowdown with the default of enabled CRC checks

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>