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/

Mechanically convert if_xae to IfAPI

Reviewed by: zlei
Sponsored by: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D37797

xilinx: Remove unused devclass arguments to DRIVER_MODULE.

Remove unused miibus_devclass and miibus_fdt_devclass.

if_xae: Remove unused variables.

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

Enter the network epoch in the xdma interrupt handler if required
by a peripheral device driver.

Sponsored by: DARPA, AFRL

Fix xae(4) driver attachement on the Government Furnished Equipment (GFE)
riscv cores.

GFE cores come with standard DTS file that lacks standard 'dmas ='
property, which means xae(4) could not find a DMA controller to use.

The 'dmas' property could not be added to the DTS file because the
ethernet controller and DMA engine parts in Linux are implemented
in a single driver.

Instead of 'dmas' property the standard Xilinx 'axistream-connected'
property is provided, so fallback to use it instead.

Suggested by: James Clarke <jrtc27@jrtc27.com>
Reviewed by: James Clarke <jrtc27@jrtc27.com>
Sponsored by: DARPA, AFRL

Convert to if_foreach_llmaddr() KPI.

Add driver for Xilinx AXI Ethernet tri-mode (10/100/1000 Mb/s) MAC found
in the U.S. Government Furnished Equipment (GFE) 64-bit RISC-V cores.

Sponsored by: DARPA, AFRL