recovery: Support board-specified font sizes and font-files

This, for example, is for an LDPI device:
BOARD_RECOVERY_FONT_INCLUDE_HEADER := ../../device/geeksphone/one/font_7x16.h
BOARD_RECOVERY_FONT_WIDTH := 7
BOARD_RECOVERY_FONT_HEIGHT := 16

Change-Id: I71d2f420b9668b5767c9b0b5d90e3e523c56e873
diff --git a/ui.c b/ui.c
index df52c7e..644ea96 100644
--- a/ui.c
+++ b/ui.c
@@ -41,8 +41,13 @@
 #define MENU_MAX_COLS 64
 #define MENU_MAX_ROWS 250
 
-#define CHAR_WIDTH 10
-#define CHAR_HEIGHT 18
+#ifndef BOARD_LDPI_RECOVERY
+  #define CHAR_WIDTH 10
+  #define CHAR_HEIGHT 18
+#else
+  #define CHAR_WIDTH 7
+  #define CHAR_HEIGHT 16
+#endif
 
 #define PROGRESSBAR_INDETERMINATE_STATES 6
 #define PROGRESSBAR_INDETERMINATE_FPS 15