LinuxKPI: Add ACPI_ID_LEN const to linux/mod_devicetable.h

Sponsored by: Serenity Cyber Security, LLC
Reviewed by: emaste
MFC after: 1 week

sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

linuxkpi: Include linux/types.h in linux/mod_devicetable.h

It's done like this in linux too.

Sponsored by: Beckhoff Automation GmbH & Co. KG

linuxkpi: Declare missing `DMI_*` enum entries

Reviewed by: manu
Approved by: manu
Differential Revision: https://reviews.freebsd.org/D38532

linuxkpi: Add I2C_NAME_SIZE and I2C_MODULE_PREFIX defines

Both are needed by drm-kmod

Obtained from: drm-kmod
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: //reviews.freebsd.org/D36212

linuxkpi/dmi: don't match exactly on DMI_MATCH

Linux has two defines to check dmi data. DMI_MATCH checks if the dmi
string includes substr. DMI_EXACT_MATCH checks if the dmi string exactly
matches substr. Compat layer should have the same behaviour.

The new definition of dmi_strmatch shouldn't break any driver. A driver
would break if it uses the highest bit of the slot field. Nevertheless,
linux uses the same definition and FreeBSD uses dmi_field values as slot
which are lower than 128.

Sponsored by: Beckhoff Automation GmbH & Co. KG
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D35395

LinuxKPI: Constantly use _LINUXKPI_ prefix in include guards

MFC after: 1 week
Reviewed by: bz, emaste, hselasky, manu
Differential Revision: https://reviews.freebsd.org/D33562

linuxkpi: Add dmi_* function

dmi function are used to get smbios values.
The DRM subsystem and drivers use it to enabled (or not) quirks.

Reviewed by: hselasky
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D26046