Make out-of-memory handling more uniform

Make out-of-memory handling more uniform

This fixes one real bug in dumpstr().

* defs.h: Declare die_out_of_memory().
* strace.c (die_out_of_memory): New function.
(strace_popen): If allocation fails, call die_out_of_memory().
(main): Likewise.
(expand_tcbtab): Likewise.
(rebuild_pollv): Likewise.
* count.c (count_syscall): Likewise.
(call_summary_pers): Likewise.
* desc.c (decode_select): Likewise.
* file.c (sys_getdents): Likewise.
(sys_getdents64): Likewise.
(sys_getdirentries): Likewise.
* pathtrace.c (pathtrace_match): Likewise.
* syscall.c (qualify): Likewise.
* util.c (printstr): Likewise.
(dumpiov): Likewise.
(dumpstr): Likewise.
(fixvfork): Likewise.
* mem.c (sys_mincore): Don't check free() parameter for NULL.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>