Change FT897 write_delay to 5ms -- MicroHam seems to need it

https://github.com/Hamlib/Hamlib/issues/384

rigs/yaesu/ft897.h

@@ -32,7 +32,7 @@
 /*
  * No need to wait between written characters.
  */
-#define FT897_WRITE_DELAY		0
+#define FT897_WRITE_DELAY		5
 
 /*
  * Wait 'delay' milliseconds after writing a command sequence.