modpost: add missing else to the "of" check

stable inclusion
from stable-v5.10.198
commit 6e3d9e5caba870287b857e59c4858fd0e90290cb
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I987V5

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6e3d9e5caba870287b857e59c4858fd0e90290cb



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[ Upstream commit cbc3d00c ]

Without this 'else' statement, an "usb" name goes into two handlers:
the first/previous 'if' statement _AND_ the for-loop over 'devtable',
but the latter is useless as it has no 'usb' device_id entry anyway.

Tested with allmodconfig before/after patch; no changes to *.mod.c:

    git checkout v6.6-rc3
    make -j$(nproc) allmodconfig
    make -j$(nproc) olddefconfig

    make -j$(nproc)
    find . -name '*.mod.c' | cpio -pd /tmp/before

    # apply patch

    make -j$(nproc)
    find . -name '*.mod.c' | cpio -pd /tmp/after

    diff -r /tmp/before/ /tmp/after/
    # no difference

Fixes: acbef7b7 ("modpost: fix module autoloading for OF devices with generic compatible property")
Signed-off-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>