nvme: pci: Enable for SPL

Enable NVME and PCI NVMe drivers for SPL builds. Also enable PCI_PNP
for SPL which is required to auto configure the PCIe devices.

Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com>
diff --git a/drivers/Makefile b/drivers/Makefile
index 29be78a..78dcf62 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -35,6 +35,7 @@
 obj-$(CONFIG_$(SPL_)REMOTEPROC) += remoteproc/
 obj-$(CONFIG_$(SPL_)SYSINFO) += sysinfo/
 obj-$(CONFIG_$(SPL_TPL_)TPM) += tpm/
+obj-$(CONFIG_$(SPL_)NVME) += nvme/
 obj-$(CONFIG_XEN) += xen/
 obj-$(CONFIG_$(SPL_)FPGA) += fpga/
 obj-y += bus/