x86/boot/compressed: Avoid touching ECX in startup32_set_idt_entry()

commit 6aac80a8

 upstream.

Avoid touching register %ecx in startup32_set_idt_entry(), by folding
the MOV, SHL and ORL instructions into a single ORL which no longer
requires a temp register.

This permits ECX to be used as a function argument in a subsequent
patch.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20221122161017.2426828-10-ardb@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>