* sysdeps/posix/readv.c: Include <errno.h>, use __set_errno macro.

* sysdeps/posix/readv.c: Include <errno.h>, use __set_errno macro.

	* sysdeps/posix/writev.c: Likewise.
	From Momchil Velikov <velco@fadata.bg>.

	* elf/dl-error.c [! _LIBC_REENTRANT]: Use a static variable instead of
	calling *GL(dl_error_catch_tsd) for a thread-local location.
	* elf/rtld.c (startup_error_tsd): Conditionalize on [_LIBC_REENTRANT].
	(dl_main): Same for GL(dl_error_catch_tsd) initialization.
	* elf/dl-tsd.c: Conditionalize contents on [_LIBC_REENTRANT].

	* libio/iofflush.c: Add libc_hidden_def.
	* libio/iofwrite.c: Likewise.
	* sysdeps/generic/sigtimedwait.c: Likewise.
	* sysdeps/generic/sigwaitinfo.c: Likewise.
	* sysdeps/posix/sigwait.c: Likewise.
	Reported by Momchil Velikov <velco@fadata.bg>.

	* inet/inet_lnaof.c (inet_lnaof): Change return type to in_addr_t
	to match <arpa/inet.h> declaration.
	* inet/inet_netof.c (inet_netof): Likewise.
	* inet/inet_mkadr.c (inet_makeaddr): Likewise for argument types.
	Reported by Momchil Velikov <velco@fadata.bg>.