for-each-ref: correct spelling of Tcl in option description
for-each-ref: correct spelling of Tcl in option description

Tcl is conventionally spelled "Tcl". The description of
option "--tcl", however, spells it "tcl". Let's follow
the convention.

Reported-by: Hartmut Henkel <5e07529257ac64421a7abe0f150c013a0a4ba688@gmx.de>
Signed-off-by: Ralf Thielow <d790fea1760bfa57e221e3da971e544c5c4e0598@gmail.com>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git