Fix some compiler warnings in libpixelflinger.

class/struct mismatch and use of 'register'.

Change-Id: I6cfe0f7fdc214c3a009eb01251f5ea9a8fdb895d
diff --git a/libpixelflinger/trap.cpp b/libpixelflinger/trap.cpp
index 80efeff..ea53625 100644
--- a/libpixelflinger/trap.cpp
+++ b/libpixelflinger/trap.cpp
@@ -563,10 +563,10 @@
     
     c->init_y(c, miny);
     for (int32_t y = miny; y < maxy; y++) {
-        register int32_t ex0 = ey0;
-        register int32_t ex1 = ey1;
-        register int32_t ex2 = ey2;    
-        register int32_t xl, xr;
+        int32_t ex0 = ey0;
+        int32_t ex1 = ey1;
+        int32_t ex2 = ey2;    
+        int32_t xl, xr;
         for (xl=minx ; xl<maxx ; xl++) {
             if (ex0>0 && ex1>0 && ex2>0)
                 break; // all strictly positive