fix warnings about pointer signedness

diff --git a/miscutils/less.c b/miscutils/less.c
index 37ec5d9..065bf6f 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -731,7 +731,7 @@
  again:
 	less_gets_pos = pos;
 	memset(input, 0, sizeof(input));
-	getch_nowait(input, sizeof(input));
+	getch_nowait((char *)input, sizeof(input));
 	less_gets_pos = -1;
 
 	/* Detect escape sequences (i.e. arrow keys) and handle