Do not suppress signal delivery messages with -qq

Current implementation of -qq does not allow suppressing exit status
messages without suppressing signal delivery messages, which is not
good.  There is a traditional "-e signal=none" syntax that can be used
to suppress all signal delivery messages.
This partially reverts commit v4.7-222-g01997cf.

* strace.c (trace): Do not suppress signal delivery messages with -qq.
* strace.1: Update documentation about -qq option.
2 files changed