bsd.own.mk: rename GCC_NO_* to CC_WNO_*

Rename compiler-warning-disable variables from
GCC_NO_warning
to
CC_WNO_warning
where warning is the full warning name as used by the compiler.

GCC_NO_IMPLICIT_FALLTHRU is CC_WNO_IMPLICIT_FALLTHROUGH

Using the convention CC_compilerflag, where compilerflag
is based on the full compiler flag name.

introduce some common variables for use in GCC warning disables:

GCC_NO_FORMAT_TRUNCATION -Wno-format-truncation (GCC 7/8)
GCC_NO_STRINGOP_TRUNCATION -Wno-stringop-truncation (GCC 8)
GCC_NO_STRINGOP_OVERFLOW -Wno-stringop-overflow (GCC 8)
GCC_NO_CAST_FUNCTION_TYPE -Wno-cast-function-type (GCC 8)

use these to turn off warnings for most GCC-8 complaints. many
of these are false positives, most of the real bugs are already
commited, or are yet to come.


we plan to introduce versions of (some?) of these that use the
"-Wno-error=" form, which still displays the warnings but does
not make it an error, and all of the above will be re-considered
as either being "fix me" (warning still displayed) or "warning
is wrong."

branches: 1.13.26;
WARNS=5

branches: 1.12.6; 1.12.12;
Enable WARNS=4 by default for usr.bin, except for:
awk bdes checknr compile_et error gss hxtool kgetcred kinit
klist ldd less lex locale login m4 man menuc mk_cmds
mklocale msgc openssl rpcgen rpcinfo sdiff spell ssh
string2key telnet tn3270 verify_krb5_conf xlint

branches: 1.11.42;
Now that <bsd.prog.mk> DTRT if HOSTPROG is defined (i.e, it is a no-op),
there's no need to special-case .include-ing it.

Add hooks to allow toolchain bits to be reachover-built at the top level.

Remove -g.

Add a -M flag, for generating thread-safe stubs, per RedHat.
Also clean up some KNF and ANSI C glitches in -Sc and -Ss output.

remove CFLAGS+=-g

branches: 1.6.2;
remove WARNS=1

- Rename "inline" variable to "doinline" so that we don't need -ansi
- Fix gcc warnings and add netbsd rcsid's
- add WARNS to the Makefile
- Add errx() to unhandled cases where appropriate.

Clean up import & propagate NetBSD changes.
Add RCS Ids.
Fix a number of bugs.
Note: this version supports ANSI C code generation.

rpcgen is just a protocol compiler, it doesn't need -lrpc

Add RCS identifiers, remove some completely useless RCS logs and patchkit
headers, and a few other insignificant changes.

branches: 1.1.1;
Added rpcgen(1)