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/minui/Android.mk b/minui/Android.mk
index 91dd939..10f0f3f 100644
--- a/minui/Android.mk
+++ b/minui/Android.mk
@@ -7,6 +7,10 @@
     external/libpng\
     external/zlib
 
+ifneq ($(BOARD_LDPI_RECOVERY),)
+    LOCAL_CFLAGS += -DBOARD_LDPI_RECOVERY='"$(BOARD_LDPI_RECOVERY)"'
+endif
+
 LOCAL_MODULE := libminui
 
 include $(BUILD_STATIC_LIBRARY)