[PATCH current v6.16] mux: mmio: Fix missing CONFIG_REGMAP_MMIO

[Krzysztof Kozlowski]

MMIO mux uses now regmap_init_mmio(), so one way or another
CONFIG_REGMAP_MMIO should be enabled, because there are no stubs for
!REGMAP_MMIO case:

  ERROR: modpost: "__regmap_init_mmio_clk" [drivers/mux/mux-mmio.ko] undefined!

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202505150312.dYbBqUhG-lkp@xxxxxxxxx/
Fixes: 61de83fd8256 ("mux: mmio: Do not use syscon helper to build regmap")
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
Link: https://lore.kernel.org/r/20250521152354.92720-2-krzysztof.kozlowski@xxxxxxxxxx
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
---

Hi Greg,

This fixes compile test build isssues reported for commit introduced in
this merge window.  

 drivers/mux/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index 80f015cf6e54..c68132e38138 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -48,6 +48,7 @@ config MUX_GPIO
 config MUX_MMIO
 	tristate "MMIO/Regmap register bitfield-controlled Multiplexer"
 	depends on OF
+	select REGMAP_MMIO
 	help
 	  MMIO/Regmap register bitfield-controlled Multiplexer controller.
 
-- 
2.45.2