Implement #64517: Add AC_ARG_PROGRAM macro

The AC_ARG_PROGRAM Autoconf macro provides program name transformations
when installing. This patch implements #64517 and prepares the
implementation for the request #60518.

In ./configure --help it additionally outputs --program-prefix=PREFIX,
--program-suffix=SUFFIX and the upcoming --program-transform-name=PROGRAM
option.

Macro AC_ARG_PROGRAM is available since Autoconf 2.0 and needs to be
called after the AC_CANONICAL_TARGET macro.

Refs:
- https://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Transforming-Names.html

Author: petk

UPGRADING.INTERNALS

@@ -27,6 +27,8 @@ PHP 7.4 INTERNALS UPGRADE NOTES
 ========================
 
   a. Unix build system changes
+    - configure --help now also outputs --program-suffix and --program-prefix
+      information by using the Autoconf AC_ARG_PROGRAM macro.
 
   b. Windows build system changes
 

configure.ac

@@ -1207,6 +1207,8 @@ EXTRA_LDFLAGS_PROGRAM="$EXTRA_LDFLAGS_PROGRAM $LDFLAGS"
 EXTRA_LIBS="$EXTRA_LIBS $LIBS"
 unset LIBS LDFLAGS
 
+AC_ARG_PROGRAM
+
 test "$prefix" = "NONE" && prefix=/usr/local
 test "$exec_prefix" = "NONE" && exec_prefix='${prefix}'
 test "$program_prefix" = "NONE" && program_prefix=