Fix "format not a string literal" warning caused by tprintf(str)

Fix "format not a string literal" warning caused by tprintf(str)

* defs.h: Declare tprints().
* strace.c: Define tprints().
(tabto): Use tprints(str), since tprintf(str) was throwing a warning.
* desc.c: Use tprints(str) instead of tprintf("%s", str).
* file.c: Likewise.
* io.c: Likewise.
* net.c: Likewise.
* process.c: Likewise.
* signal.c: Likewise.
* syscall.c: Likewise.
* util.c: Likewise.

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