command: Don't pass max_size to command_encodef()

The command_encodef() can read the max_size parameter directly from
the 'struct command_encoder' passed into it.  Also, there is no need
to check that a message will fit in a buffer if the buffer is declared
to be MESSAGE_MAX in size.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

src/pru/internal.h

@@ -3,6 +3,7 @@
 // Local definitions for PRU code
 
 #include <stdint.h> // uint32_t
+#include "command.h" // MESSAGE_MAX
 
 #define IEP_EVENT                 7
 #define KICK_ARM_EVENT            16
@@ -24,7 +25,7 @@
 // Layout of shared memory
 struct shared_response_buffer {
     uint32_t count;
-    char data[64];
+    char data[MESSAGE_MAX];
 };
 struct shared_mem {
     uint32_t signal;