Fix various typos, scattered over the code.
Spelling corrections for (among other things):
* environment
* override
* variable
* ftd (should be "fdt", for flattened device tree)
* embedded
* FTDI
* emulation
* controller
diff --git a/doc/SPI/README.sandbox-spi b/doc/SPI/README.sandbox-spi
index bb73eaf..dfa845c 100644
--- a/doc/SPI/README.sandbox-spi
+++ b/doc/SPI/README.sandbox-spi
@@ -1,7 +1,7 @@
Sandbox SPI/SPI Flash Implementation
====================================
-U-Boot supports SPI and SPI flash emuation in sandbox. This must be enabled
+U-Boot supports SPI and SPI flash emulation in sandbox. This must be enabled
using the --spi_sf paramter when starting U-Boot.
For example: