sh: Move board specific options into the Board support menu

Move the sourcing of the board specific Kconfig files into the
"Board support" menu. Without this they appear underneath the
"Board support" menu, in the "System type" menu.

[lethal@linux-sh.org: handle the magicpanelr2 case, too]
Signed-off-by: NStuart Menefy <stuart.menefy@st.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/boards/Kconfig

@@ -338,8 +338,6 @@ config SH_APSH4AD0A
 	help
 	  Select AP-SH4AD-0A if configuring for an ALPHAPROJECT AP-SH4AD-0A.
 
-endmenu
-
 source "arch/sh/boards/mach-r2d/Kconfig"
 source "arch/sh/boards/mach-highlander/Kconfig"
 source "arch/sh/boards/mach-sdk7780/Kconfig"
@@ -359,3 +357,5 @@ config SH_MAGIC_PANEL_R2_VERSION
 endmenu
 
 endif
+
+endmenu