Enable P10 HCODE and HOSTBOOT_BINARIES compilation

   - Implement makefiles for hostboot_binaries and hcode
     to build the p10 content
   - Add an override ENV Var to use a binary version of hcode
     instead of compiling the source code
   - Binary used for override is release: hw112519a.opmst10
diff --git a/openpower/configs/rainier_defconfig b/openpower/configs/rainier_defconfig
index 0b0a114..b78dced 100644
--- a/openpower/configs/rainier_defconfig
+++ b/openpower/configs/rainier_defconfig
@@ -59,7 +59,7 @@
 BR2_OPENPOWER_PNOR_FILENAME="rainier.pnor"
 BR2_HOSTBOOT_BINARY_SBE_FILENAME="p10_sbe.img.ecc"
 BR2_HOSTBOOT_BINARY_SBEC_FILENAME="centaur_sbec_pad.img.ecc"
-BR2_HOSTBOOT_BINARY_WINK_FILENAME="p9n.ref_image.hdr.bin.ecc"
+BR2_HOSTBOOT_BINARY_WINK_FILENAME="p10.ref_image.hdr.bin.ecc"
 BR2_IMA_CATALOG_FILENAME="ima_catalog.bin"
 BR2_OPENPOWER_TARGETING_BIN_FILENAME="RAINIER_HB.targeting.bin"
 BR2_OPENPOWER_TARGETING_ECC_FILENAME="RAINIER_HB.targeting.bin.ecc"