Respect --program-prefix/suffix when installing phar

Currently ./configure --enable-phar --program-suffix=7.4 will
result in binaries named php7.4 and phar but should instead
result in php7.4 and phar7.4

Closes GH-5650.

Author: n8man

ext/phar/Makefile.frag

@@ -42,9 +42,9 @@ $(builddir)/phar.phar: $(builddir)/phar.php $(builddir)/phar/phar.inc $(srcdir)/
 
 install-pharcmd: pharcmd
 	-@$(mkinstalldirs) $(INSTALL_ROOT)$(bindir)
-	$(INSTALL) $(builddir)/phar.phar $(INSTALL_ROOT)$(bindir)
-	-@rm -f $(INSTALL_ROOT)$(bindir)/phar
-	$(LN_S) -f phar.phar $(INSTALL_ROOT)$(bindir)/phar
+	$(INSTALL) $(builddir)/phar.phar $(INSTALL_ROOT)$(bindir)/$(program_prefix)phar$(program_suffix).phar
+	-@rm -f $(INSTALL_ROOT)$(bindir)/$(program_prefix)phar$(program_suffix)
+	$(LN_S) -f $(program_prefix)phar$(program_suffix).phar $(INSTALL_ROOT)$(bindir)/$(program_prefix)phar$(program_suffix)
 	@$(mkinstalldirs) $(INSTALL_ROOT)$(mandir)/man1
-	@$(INSTALL_DATA) $(builddir)/phar.1 $(INSTALL_ROOT)$(mandir)/man1/phar.1
-	@$(INSTALL_DATA) $(builddir)/phar.phar.1 $(INSTALL_ROOT)$(mandir)/man1/phar.phar.1
+	@$(INSTALL_DATA) $(builddir)/phar.1 $(INSTALL_ROOT)$(mandir)/man1/$(program_prefix)phar$(program_suffix).1
+	@$(INSTALL_DATA) $(builddir)/phar.phar.1 $(INSTALL_ROOT)$(mandir)/man1/$(program_prefix)phar$(program_suffix).phar.1