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>
diff --git a/file.c b/file.c
index 09977e9..7bf1814 100644
--- a/file.c
+++ b/file.c
@@ -386,7 +386,7 @@
 void
 tprint_open_modes(mode_t flags)
 {
-	tprintf("%s", sprint_open_modes(flags) + sizeof("flags"));
+	tprints(sprint_open_modes(flags) + sizeof("flags"));
 }
 
 static int