tweaks: remove two superfluous includes

The precalculation of the multiline regexes no longer looks at the
keyboard every second, and the backup code makes use of futimens()
nowadays.

src/color.c

@@ -24,7 +24,6 @@
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>
-#include <time.h>
 #include <unistd.h>
 
 #ifdef HAVE_MAGIC_H

src/files.c

@@ -25,7 +25,6 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <utime.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <ctype.h>