[yocto] [meta-raspberrypi][PATCH 4/4] README: Document new variable configuration

[Theodor Gherzan]

From: Theodor Gherzan <theodor at resin.io>

Signed-off-by: Theodor Gherzan <theodor at resin.io>
---
 README | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/README b/README
index ec9f905..ee330df 100644
--- a/README
+++ b/README
@@ -29,6 +29,7 @@ Contents:
     3.L. Enable SPI bus
     3.M. Enable I2C
     3.N. Enable PiTFT support
+    3.O. Enable UART support
 4. Extra apps
     4.A. omxplayer
 5. Board Configuration
@@ -238,6 +239,12 @@ List of currently supported models:
     - pitft22
     - pitft28r
 
+3.O. Enable UART
+===============
+Set this variable to enable UART on raspberypi3:
+ENABLE_UART = "1"
+
+Note: The value of enable_uart would be set to 1 by default on raspberrypi 1/2.
 
 4. Extra apps
 =============
-- 
2.1.4