armv8: fsl-layerscape: fix compile warning "rcw_tmp"

arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch2_speed.c: In function
‘get_sys_info’:
arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch2_speed.c:29:6: warning:
unused variable ‘rcw_tmp’ [-Wunused-variable]
  u32 rcw_tmp;
Signed-off-by: NPrabhakar Kushwaha <prabhakar.kushwaha@nxp.com>
Reviewed-by: NYork Sun <york.sun@nxp.com>

arch/arm/cpu/armv8/fsl-layerscape/fsl_lsch2_speed.c

@@ -25,7 +25,10 @@ void get_sys_info(struct sys_info *sys_info)
 	struct fsl_ifc ifc_regs = {(void *)CONFIG_SYS_IFC_ADDR, (void *)NULL};
 	u32 ccr;
 #endif
-#if defined(CONFIG_FSL_ESDHC) || defined(CONFIG_SYS_DPAA_FMAN)
+#if (defined(CONFIG_FSL_ESDHC) &&\
+	defined(CONFIG_FSL_ESDHC_USE_PERIPHERAL_CLK)) ||\
+	defined(CONFIG_SYS_DPAA_FMAN)
+
 	u32 rcw_tmp;
 #endif
 	struct ccsr_clk *clk = (void *)(CONFIG_SYS_FSL_CLK_ADDR);