doc: Fix some typos in different files

adresses/addresses
alernate/alternate
asssuming/assuming
calcualted/calculated
enviroment/environment
evalutation/evaluation
falsh/flash
labled/labeled
paramaters/parameters

Signed-off-by: Thomas Weber <thomas@tomweber.eu>
Acked-by: Anatolij Gustschin <agust@denx.de>
diff --git a/doc/README.SNTP b/doc/README.SNTP
index 9edc957..da9ec45 100644
--- a/doc/README.SNTP
+++ b/doc/README.SNTP
@@ -6,7 +6,7 @@
 parameter of server's IP address or environment variable
 "ntpserverip". The network time is sent as UTC. So if you want to
 set local time to RTC, set the offset in second from UTC to the
-enviroment variable "time offset".
+environment variable "time offset".
 
 If the DHCP server provides time server's IP or time offset, you
 don't need to set the above environment variables yourself.