patch 8.0.0576: can't build when configure choses "install-sh"

Problem:    Can't build when configure choses "install-sh". (Daniel Hahler)
Solution:   Always use install-sh.  Fix remaining use of mkinstalldirs.
            (closes #1647)

src/auto/configure

@@ -725,7 +725,6 @@ XCODE_SELECT
 CPP_MM
 CROSS_COMPILING
 STRIP
-MKDIR_P
 AWK
 FGREP
 EGREP
@@ -3886,76 +3885,6 @@ fi
 
   test -n "$AWK" && break
 done
-		ac_aux_dir=
-for ac_dir in "$srcdir" "$srcdir/.." "$srcdir/../.."; do
-  if test -f "$ac_dir/install-sh"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/install-sh -c"
-    break
-  elif test -f "$ac_dir/install.sh"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/install.sh -c"
-    break
-  elif test -f "$ac_dir/shtool"; then
-    ac_aux_dir=$ac_dir
-    ac_install_sh="$ac_aux_dir/shtool install -c"
-    break
-  fi
-done
-if test -z "$ac_aux_dir"; then
-  as_fn_error $? "cannot find install-sh, install.sh, or shtool in \"$srcdir\" \"$srcdir/..\" \"$srcdir/../..\"" "$LINENO" 5
-fi
-
-# These three variables are undocumented and unsupported,
-# and are intended to be withdrawn in a future Autoconf release.
-# They can cause serious problems if a builder's source tree is in a directory
-# whose full name contains unusual characters.
-ac_config_guess="$SHELL $ac_aux_dir/config.guess"  # Please don't use this var.
-ac_config_sub="$SHELL $ac_aux_dir/config.sub"  # Please don't use this var.
-ac_configure="$SHELL $ac_aux_dir/configure"  # Please don't use this var.
-
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for a thread-safe mkdir -p" >&5
-$as_echo_n "checking for a thread-safe mkdir -p... " >&6; }
-if test -z "$MKDIR_P"; then
-  if ${ac_cv_path_mkdir+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
-for as_dir in $PATH$PATH_SEPARATOR/opt/sfw/bin
-do
-  IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_prog in mkdir gmkdir; do
-	 for ac_exec_ext in '' $ac_executable_extensions; do
-	   as_fn_executable_p "$as_dir/$ac_prog$ac_exec_ext" || continue
-	   case `"$as_dir/$ac_prog$ac_exec_ext" --version 2>&1` in #(
-	     'mkdir (GNU coreutils) '* | \
-	     'mkdir (coreutils) '* | \
-	     'mkdir (fileutils) '4.1*)
-	       ac_cv_path_mkdir=$as_dir/$ac_prog$ac_exec_ext
-	       break 3;;
-	   esac
-	 done
-       done
-  done
-IFS=$as_save_IFS
-
-fi
-
-  test -d ./--version && rmdir ./--version
-  if test "${ac_cv_path_mkdir+set}" = set; then
-    MKDIR_P="$ac_cv_path_mkdir -p"
-  else
-    # As a last resort, use the slow shell script.  Don't cache a
-    # value for MKDIR_P within a source directory, because that will
-    # break other packages using the cache if that directory is
-    # removed, or if the value is a relative name.
-    MKDIR_P="$ac_install_sh -d"
-  fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $MKDIR_P" >&5
-$as_echo "$MKDIR_P" >&6; }
 
 # Extract the first word of "strip", so it can be a program name with args.
 set dummy strip; ac_word=$2
@@ -14785,7 +14714,6 @@ gives unlimited permission to copy, distribute and modify it."
 
 ac_pwd='$ac_pwd'
 srcdir='$srcdir'
-MKDIR_P='$MKDIR_P'
 AWK='$AWK'
 test -n "\$AWK" || AWK=awk
 _ACEOF
@@ -15343,11 +15271,6 @@ ac_abs_srcdir=$ac_abs_top_srcdir$ac_dir_suffix
   # CONFIG_FILE
   #
 
-  ac_MKDIR_P=$MKDIR_P
-  case $MKDIR_P in
-  [\\/$]* | ?:[\\/]* ) ;;
-  */*) ac_MKDIR_P=$ac_top_build_prefix$MKDIR_P ;;
-  esac
 _ACEOF
 
 cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
@@ -15401,7 +15324,6 @@ s&@abs_top_srcdir@&$ac_abs_top_srcdir&;t t
 s&@builddir@&$ac_builddir&;t t
 s&@abs_builddir@&$ac_abs_builddir&;t t
 s&@abs_top_builddir@&$ac_abs_top_builddir&;t t
-s&@MKDIR_P@&$ac_MKDIR_P&;t t
 $ac_datarootdir_hack
 "
 eval sed \"\$ac_sed_extra\" "$ac_file_inputs" | $AWK -f "$ac_tmp/subs.awk" \