drivers: mmc: rpmb: do not build for SPL

RPMB support is used by the 'mmc rpmb' command and by the OP-TEE support.
We do not need it in SPL.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 615b724..e84c792 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -38,7 +38,7 @@
 obj-$(CONFIG_MMC_MXS)			+= mxsmmc.o
 obj-$(CONFIG_MMC_PCI)			+= pci_mmc.o
 obj-$(CONFIG_PXA_MMC_GENERIC) += pxa_mmc_gen.o
-obj-$(CONFIG_SUPPORT_EMMC_RPMB) += rpmb.o
+obj-$(CONFIG_$(SPL_TPL_)SUPPORT_EMMC_RPMB) += rpmb.o
 obj-$(CONFIG_MMC_SANDBOX)		+= sandbox_mmc.o
 obj-$(CONFIG_SH_MMCIF) += sh_mmcif.o
 obj-$(CONFIG_SH_SDHI) += sh_sdhi.o