new in linux commmit cdf4969c42a6c1a376dd03a9e846cf638d3cd4b1

With Linux kernel 4.16 it will be possible to guard more parts of the
Linux header files from a libc. Make use of this in musl to guard all
the structures and other definitions from the Linux header files which
are also defined by the header files provided by musl. This will make
it possible to compile source files which include both the libc
headers and the kernel userspace headers.

This extends the definitions done in commit 04983f22 ("make
netinet/in.h suppress clashing definitions from kernel headers")

new in linux commit 531b374834c891ae2abf800693074df35a7d1a36

ARPHRD_6LOWPAN (IPv6 over LoWPAN) added in
linux 3.14 commit 0abc652c796dab74d34d60473ec5594cd21620be

glibc, freebsd, and openbsd use character pointers (caddr_t) for
these fields. only linux uses void pointer for the ifru_data type.

placing the opening brace on the same line as the struct keyword/tag
is the style I prefer and seems to be the prevailing practice in more
recent additions.

these changes were generated by the command:

find include/ arch/*/bits -name '*.h' \
-exec sed -i '/^struct [^;{]*$/{N;s/\n/ /;}' {} +

and subsequently checked by hand to ensure that the regex did not pick
up any false positives.

the removed ARPHRD_IEEE802154_PHY was only present in the kernel api
in v2.6.31 (by accident), but it got into the glibc headers (in 2009)
and remained there since this header was not updated since then.

the old behavior of exposing nothing except plain ISO C can be
obtained by defining __STRICT_ANSI__ or using a compiler option (such
as -std=c99) that predefines it. the new default featureset is POSIX
with XSI plus _BSD_SOURCE. any explicit feature test macros will
inhibit the default.

installation docs have also been updated to reflect this change.

one file was reusing another file's macro name, and many had
inconsistent underscores and application of SYS prefix, etc.

patch by Szabolcs Nagy (nsz)

patch by Isaac Dunham. matched closely (maybe not exact) to glibc's
idea of what _BSD_SOURCE should make visible.

patch by Arvid Picciani (aep)