ppc: arm: Move sdhc_clk into arch_global_data

This is used by both powerpc and arm, but I think it still qualifies as
architecture-specific.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/powerpc/cpu/mpc83xx/speed.c b/arch/powerpc/cpu/mpc83xx/speed.c
index ba8b285..6be0e3a 100644
--- a/arch/powerpc/cpu/mpc83xx/speed.c
+++ b/arch/powerpc/cpu/mpc83xx/speed.c
@@ -478,7 +478,7 @@
 	gd->arch.tdm_clk = tdm_clk;
 #endif
 #if defined(CONFIG_FSL_ESDHC)
-	gd->sdhc_clk = sdhc_clk;
+	gd->arch.sdhc_clk = sdhc_clk;
 #endif
 	gd->arch.core_clk = core_clk;
 	gd->arch.i2c1_clk = i2c1_clk;
@@ -570,7 +570,8 @@
 	       strmhz(buf, gd->arch.tdm_clk));
 #endif
 #if defined(CONFIG_FSL_ESDHC)
-	printf("  SDHC:                %-4s MHz\n", strmhz(buf, gd->sdhc_clk));
+	printf("  SDHC:                %-4s MHz\n",
+	       strmhz(buf, gd->arch.sdhc_clk));
 #endif
 #if defined(CONFIG_MPC8308) || defined(CONFIG_MPC831x) || \
 	defined(CONFIG_MPC834x) || defined(CONFIG_MPC837x)