scripts/mkmakefile: fix typo

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

scripts/mkmakefile

@@ -1,7 +1,7 @@
 #!/bin/sh
 # Generates a small Makefile used in the root of the output
 # directory, to allow make to be started from there.
-# The Makefile also allow for more convinient build of external modules
+# The Makefile also allow for more convenient build of external modules
 
 # Usage
 # $1 - Kernel src directory