sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

bhnd: clean up empty lines in .c and .h files

Avoid relying on header pollution from sys/refcount.h.

MFC after: 3 days
Sponsored by: The FreeBSD Foundation

bhnd(4): support direct conversion of bhnd_nvram_val

This adds support for bhnd_nvram_val_convert_init() and
bhnd_nvram_val_convert_new(), which may be used to perform value
format-aware encoding of an NVRAM value to a new target format/type.

This will be used to simplify converting to/from serialized
format-specific NVRAM value representations to common external
representations.

Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D8757

bhnd(4): minor style(9) fixes

Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D8755

bhnd(4): Unify NVRAM/SPROM parsing, implement compact SPROM layout encoding.


- Defined an abstract NVRAM I/O API (bhnd_nvram_io), decoupling NVRAM/SPROM
parsing from the actual underlying NVRAM data provider (e.g. CFE firmware
devices).
- Defined an abstract NVRAM data API (bhnd_nvram_data), decoupling
higher-level NVRAM operations (indexed lookup, data conversion, etc) from
the underlying NVRAM file format parsing/serialization.
- Implemented a new high-level bhnd_nvram_store API, providing indexed
variable lookup, pending write tracking, etc on top of an arbitrary
bhnd_nvram_data instance.
- Migrated all bhnd(4) NVRAM device drivers to the common bhnd_nvram_store
API.
- Implemented a common bhnd_nvram_val API for parsing/encoding NVRAM
variable values, including applying format-specific behavior when
converting to/from the NVRAM string representations.
- Dropped the now unnecessary bhnd_nvram driver, and moved the
broadcom/mips-specific CFE NVRAM driver out into sys/mips/broadcom.
- Implemented a new nvram_map file format:
- Variable definitions are now defined separately from the SPROM
layout. This will also allow us to define CIS tuple NVRAM
mappings referencing the common NVRAM variable definitions.
- Variables can now be defined within arbitrary named groups.
- Textual descriptions and help information can be defined inline
for both variables and variable groups.
- Implemented a new, compact encoding of SPROM image layout
offsets.
- Source-level (but not build system) support for building the NVRAM file
format APIs (bhnd_nvram_io, bhnd_nvram_data, bhnd_nvram_store) as a
userspace library.

The new compact SPROM image layout encoding is loosely modeled on Apple
dyld compressed LINKEDIT symbol binding opcodes; it provides a compact
state-machine encoding of the mapping between NVRAM variables and the SPROM
image offset, mask, and shift instructions necessary to decode or encode
the SPROM variable data.

The compact encoding reduces the size of the generated SPROM layout data
from roughly 60KB to 3KB. The sequential nature SPROM layout opcode tables
also simplify iteration of the SPROM variables, as it's no longer
neccessary to iterate the full NVRAM variable definition table, but
instead simply scan the SPROM revision's layout opcode table.

Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D8645