patch 9.0.1793: obsolete macros in configure script

Problem:  obsolete macros in configure script
Solution: Remove those and start moving to autoconf 2.71

src/configure.ac: Remove obsolete macros

These macros are declared obsolete in autoconf 2.69, which is almost 10
years old by now:

  https://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Obsolete-Macros.html

They generate warnings when in a subsequent upgrade to autoconf 2.71.

`autoupdate` from autoupdate 2.71 suggests most of these changes, except
that it also adds obsolete warnings, that where individually checked and
removed.

Regenerated `src/auto/configure` by running:

  cd src
  autoconf2.69 --output=auto/configure configure.ac
  sed --in-place --expression='s@>config.log@>auto/config.log@g' auto/configure

closes: #12888

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Illia Bobyr <illia.bobyr@gmail.com>
diff --git a/src/configure.ac b/src/configure.ac
index 6813d76..d753ffe 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -4,7 +4,8 @@
 dnl This should also work with other versions of autoconf, but 2.70 and later
 dnl generate lots of hard to fix "obsolete" warnings.
 
-AC_INIT(vim.h)
+AC_INIT
+AC_CONFIG_SRCDIR([vim.h])
 AC_CONFIG_HEADERS(auto/config.h:config.h.in)
 
 dnl Being able to run configure means the system is Unix (compatible).
@@ -14,9 +15,8 @@
 dnl Checks for programs.
 AC_PROG_CC_C99		dnl required by almost everything
 AC_PROG_CPP		dnl required by header file checks
-AC_PROGRAM_EGREP	dnl required by AC_EGREP_CPP
+AC_PROG_EGREP		dnl required by AC_EGREP_CPP
 AC_PROG_FGREP		dnl finds working grep -F
-AC_ISC_POSIX		dnl required by AC_C_CROSS
 AC_PROG_AWK		dnl required for "make html" in ../doc
 
 dnl Don't strip if we don't have it
@@ -3354,7 +3354,8 @@
 AC_TYPE_UID_T
 AC_TYPE_UINT32_T
 
-AC_HEADER_TIME
+AC_CHECK_HEADERS_ONCE([sys/time.h])
+
 AC_CHECK_TYPE(ino_t, long)
 AC_CHECK_TYPE(dev_t, unsigned)
 AC_C_BIGENDIAN(,,,)
@@ -3605,8 +3606,6 @@
 			AC_DEFINE(SYS_SELECT_WITH_SYS_TIME),
 	  AC_MSG_RESULT(no))
 
-dnl AC_DECL_SYS_SIGLIST
-
 dnl Checks for pty.c (copied from screen) ==========================
 AC_MSG_CHECKING(for /dev/ptc)
 if test -r /dev/ptc; then