Eliminate MAX_QUALS, make qualifier array dynamic

Eliminate MAX_QUALS, make qualifier array dynamic

MAX_QUALS was 2048, even though most arches used less than 500 entries
in it. MAX_QUALS had to be maintained by hand to be higher than syscall
count. It also limited the highest possible fd to track.

This change makes qual_flagsN[] arrays start sized to the required minimum
(number of syscalls) and grow dynamically if user requested
-e read=BIGNUM. As a precaution, BIGNUM should be < 2^15, but this limit
can be raised with no cost for normal strace invocations.

qual_flags is now a define to qual_vec[current_personality].

As a bonus, this patch aliases sysent, errnoent, signalent, ioctlent
names in one-personality arches to their corresponding <foo>0 arrays,
removing one indirection level.

  text   data    bss    dec    hex filename
244471    700  12928 258099  3f033 strace.t7/strace
244627    680  10860 256167  3e8a7 strace.t8/strace

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