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/desc.c b/desc.c
index e77a238..5cb8a1a 100644
--- a/desc.c
+++ b/desc.c
@@ -519,7 +519,7 @@
 			tprintf(", [");
 			for (j = 0, sep = ""; j < nfds; j++) {
 				if (FD_ISSET(j, fds)) {
-					tprintf("%s", sep);
+					tprints(sep);
 					printfd(tcp, j);
 					sep = " ";
 				}