Fix version-specific configuration for compiling PHP

I have reverted dc3c12b as this was
a misunderstanding of intended behaviour. The special config files for
PHP versions use ‘master’, ‘7.2’, and ‘7.4’ as suffix.

The new MINOR_VERSION variable will convert all the following to 7.4
before looking for the file:
7.4
7.4.23
7.4snapshot

It appears as though the “7.2” file wasn’t being used without this
change, as the previous substitution command was converting
“7.2snapshot” ot “7”.

Author: Sam Minnee

.travis.yml

@@ -85,9 +85,10 @@ install:
 - ./bin/install-libsodium
 - ./bin/install-password-argon2
 - . ./bin/install-onig # sourced to export ONIG_LIBS
+- MINOR_VERSION=`echo $VERSION | sed -E 's/^([0-9]+\.[0-9]+).*$/\1/'` # Rewrites 7.2, 7.2snapshot, 7.2.13 => '7.2'. Leaves 'master' as-is
 - |
-  if [[ -f default_configure_options.$RELEASE-${VERSION%*.*} ]]; then
-    cp default_configure_options.$RELEASE-${VERSION%*.*} $HOME/.php-build/share/php-build/default_configure_options
+  if [[ -f default_configure_options.$RELEASE-$MINOR_VERSION ]]; then
+    cp default_configure_options.$RELEASE-$MINOR_VERSION $HOME/.php-build/share/php-build/default_configure_options
   else
     cp default_configure_options.$RELEASE $HOME/.php-build/share/php-build/default_configure_options
   fi