evas_drm: Move MAX_BUFFERS macro from header to source file

Summary:
It's no longer needed in the header because it doesn't change
the size of the structures there anymore.
Depends on D6564

Reviewers: devilhorns

Reviewed By: devilhorns

Subscribers: cedric, #committers, zmike

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D6565

src/modules/evas/engines/drm/evas_engine.h

@@ -41,8 +41,6 @@ extern int _evas_engine_drm_log_dom;
 # endif
 # define CRI(...) EINA_LOG_DOM_CRIT(_evas_engine_drm_log_dom, __VA_ARGS__)
 
-#define MAX_BUFFERS 10
-
 typedef struct _Outbuf_Fb
 {
    int age;

src/modules/evas/engines/drm/evas_outbuf.c

@@ -8,6 +8,8 @@
 #define GREEN_MASK 0x00ff00
 #define BLUE_MASK 0x0000ff
 
+#define MAX_BUFFERS 10
+
 static void
 _outbuf_buffer_swap(Outbuf *ob, Eina_Rectangle *rects, unsigned int count)
 {