php8: fix PHP8_GETTEXT missing icu dependency

With CONFIG_PHP8_GETTEXT php8 always gains a
dependency on a version of the 'icu' package,
however said dependency is not declared, so
on gets compilation errors when
CONFIG_PHP8_GETTEXT=y but PACKAGE_icu is not
selected.

Therefore select PACKAGE_icu when PHP8_GETTEXT is
selected.

Closes #28207

Signed-off-by: Daniel F. Dickinson <dfdpublic@wildtechgarden.ca>

Author: danielfdickinson

lang/php8/Makefile

@@ -81,6 +81,7 @@ define Package/php8/config
 
 	config PHP8_GETTEXT
 		bool "Enable gettext"
+		select PACKAGE_icu
 		default y
 
 	config PHP8_INTL