ARM: fix dereferencing misaligned pointers

Linear ring buffer generates problems on ARM when reading and writing short
pointers. This was leading to CI communication problems with VDR, resulting
with the following info in the log:
'not all devices ready after 30 seconds.'

Fixes #27. Thanks to JeroenT for report, help and testing.

Frame.cpp

@@ -55,7 +55,8 @@ void Frame::Put(void)
 {
   if (rb && mem)
   {
-    *((short *) mem) = len;
+    *mem     = len & 0xff;
+    *(mem+1) = len >> 8;
     rb->Put(mem, len + LEN_OFF);
   }
 }
@@ -70,7 +71,7 @@ unsigned char *Frame::Get(int &l)
     {
       if (c > LEN_OFF)
       {
-        int s = *((short *) data);
+        int s = *data + (*(data+1) << 8);
         if (c >= s + LEN_OFF)
         {
           l = glen = s;

README

@@ -115,8 +115,8 @@ plugin in case of problems.
 
  To Narog for implementing the multiple adapter support
 
- To Peje, Unixer, Copper, HALLO01, udobroemme, ninjagp for their patience,
- support and testing on own hardware.
+ To Peje, Unixer, Copper, HALLO01, udobroemme, ninjagp, JeroenT for their
+ patience, support and testing on own hardware.
 
  To the authors of VDR-SC plugin, FFdecsa and Oscam for their great work and
  dedication