pack-protocol.txt: fix spelling

s/paramater/parameter/.

Signed-off-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/technical/pack-protocol.txt

@@ -36,7 +36,7 @@ Git Transport
 
 The Git transport starts off by sending the command and repository
 on the wire using the pkt-line format, followed by a NUL byte and a
-hostname paramater, terminated by a NUL byte.
+hostname parameter, terminated by a NUL byte.
 
    0032git-upload-pack /project.git\0host=myserver.com\0