exynos3: Implement custom VSYNC IOCTL

* Replace crespo-based VSYNC uevent mechanism in hwcomposer
  with a custom IOCTL mechanism instead (required kernel
  modifications.

* The VSYNC uevents were spamming the Android UEventObserver
  and causing about 7% of constant CPU load

  c86856efabfa0b2981ceb47898dc5873a4998707

Improve custom VSYNC handler in hwcomposer

* only poll when necessary
* solves suspend/resume instability?

  45bf1dae7fa9057a3415151f7559e7bd2a162ead

Change-Id: Icdb5c60059e71688479d390b7b3a1f09a0315a5f
diff --git a/exynos3/s5pc110/include/sec_lcd.h b/exynos3/s5pc110/include/sec_lcd.h
index 6a3a34a..82ef42f 100755
--- a/exynos3/s5pc110/include/sec_lcd.h
+++ b/exynos3/s5pc110/include/sec_lcd.h
@@ -34,6 +34,7 @@
 #define FBIO_WAITFORVSYNC       _IO  ('F', 32)
 #define SECFB_WIN_POSITION      _IOW ('F', 203, struct secfb_user_window)
 #define S3CFB_SET_VSYNC_INT     _IOW ('F', 206, uint32_t)
+#define S3CFB_WAIT_FOR_VSYNC    _IOR ('F', 311, uint64_t)
 
 #define DEFAULT_LCD_WIDTH   (480)
 #define DEFAULT_LCD_HEIGHT  (800)