Documentation: ACPI: fix error script name

The correct script name should be 'divergence.sh' instead of
'divergences.sh'.
I didn't find divergences.sh in the path of acpica/generate/linux/.

Signed-off-by: Hao Chen <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Corbet <[e-mail]>

Documentation/driver-api/acpi/linuxized-acpica.rst

···
    # git clone https://github.com/acpica/acpica
    # git clone https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
    # cd acpica
-   # generate/linux/divergences.sh -s ../linux
+   # generate/linux/divergence.sh -s ../linux