reset: Restrict RESET_HSDK to ARC_SOC_HSDK or COMPILE_TEST

The HSDK reset driver is only useful when building for an ARC HSDK
platform.

While at it, drop the "default n", as that is the default.

Fixes: e0be864f ("ARC: reset: introduce HSDKv1 reset driver")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
[p.zabel@pengutronix.de: rebased, renamed RESET_HSDK_V1 to RESET_HSDK]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/reset/Kconfig

@@ -37,7 +37,7 @@ config RESET_BERLIN
 config RESET_HSDK
 	bool "Synopsys HSDK Reset Driver"
 	depends on HAS_IOMEM
-	default n
+	depends on ARC_SOC_HSDK || COMPILE_TEST
 	help
 	  This enables the reset controller driver for HSDK board.