[Ada] Small cleanup in the Ada.Text_IO hierarchy

[Ada] Small cleanup in the Ada.Text_IO hierarchy

gcc/ada/

	* libgnat/a-tifiio.adb (Get): Replace Current_Input with Current_In.
	* libgnat/a-tifiio__128.adb: (Get): Likewise.
	* libgnat/a-wtcoio.adb (Get): Likewise.
	(Put): Replace Current_Output with Current_Out.
	* libgnat/a-wtdeio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtdeio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtenio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtfiio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtfiio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtflio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtinio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtinio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtmoio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-wtmoio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztcoio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztdeio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztdeio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztenio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztfiio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztfiio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztflio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztinio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztinio__128.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztmoio.adb (Get): Likewise.
	(Put): Likewise.
	* libgnat/a-ztmoio__128.adb (Get): Likewise.
	(Put): Likewise.