module: Fix device table module aliases

Commit 6717e8f91db7 ("kbuild: Remove 'kmod_' prefix from
__KBUILD_MODNAME") inadvertently broke module alias generation for
modules which rely on MODULE_DEVICE_TABLE().

It removed the "kmod_" prefix from __KBUILD_MODNAME, which caused
MODULE_DEVICE_TABLE() to generate a symbol name which no longer matched
the format expected by handle_moddevtable() in scripts/mod/file2alias.c.

As a result, modpost failed to find the device tables, leading to
missing module aliases.

Fix this by explicitly adding the "kmod_" string within the
MODULE_DEVICE_TABLE() macro itself, restoring the symbol name to the
format expected by file2alias.c.

Fixes: 6717e8f91db7 ("kbuild: Remove 'kmod_' prefix from __KBUILD_MODNAME")
Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Mark Brown <broonie@kernel.org>
Reported-by: Cosmin Tanislav <demonsingur@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Cosmin Tanislav <demonsingur@gmail.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Mark Brown <broonie@kernel.org>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Link: https://patch.msgid.link/e52ee3edf32874da645a9e037a7d77c69893a22a.1760982784.git.jpoimboe@kernel.org