tpm2_createek: Correct man page example

The example
 tpm2_createek -G rsa -u ek.pub
from 'man tpm2_createek' misses to provide '-c'.

It thus fails with
 ERROR: Expected option -c

According to tools/tpm2_createek.c:441, the option must be present in
any case. Adjust the man page example accordingly.

Signed-off-by: Tobias Deiminger <tdmg@linutronix.de>

Author: haxtibal

man/tpm2_createek.1.md

@@ -94,7 +94,7 @@ tpm2_createek -G ecc384 -c 0x81010002
 
 ### Create a transient Endorsement Key, flush it, and reload it.
 ```bash
-tpm2_createek -G rsa -u ek.pub
+tpm2_createek -c ek.ctx -G rsa -u ek.pub
 
 # Check that it is loaded in transient memory
 tpm2_getcap handles-transient