Add hexN output mode

Adds support for hexN mode where N is a number in the range 1 to 4096
which defines how many hex values will be printed before a line break.

In short, it defines the width of the hex output.

In this mode, if timestamps are enabled they will be added to each hex
line.

src/options.h

@@ -94,6 +94,7 @@ struct option_t
     const char *exclude_devices;
     const char *exclude_drivers;
     const char *exclude_tids;
+    int hex_n_value;
 };
 
 extern struct option_t option;