Increase size of STACK_ENTRY_LEN

Increased from 80 to 256, this buffer is used when creating the stack
trace used within LinuxCNC. It is used quite extensible throughout the
application.

Author: havardAasen

src/emc/rs274ngc/interp_internal.hh

@@ -638,7 +638,7 @@ and is not represented here
 
 */
 #define STACK_LEN 50
-#define STACK_ENTRY_LEN 80
+#define STACK_ENTRY_LEN 256
 #define MAX_SUB_DIRS 10
 
 struct setup