conf: machine: add j721e-sk machine-configuration

As of commit [1] there will be a separate defconfig to build u-boot for
j721e-evm and j721e-sk.

Hence, introduce new yocto machine configs for j721e-sk.

[1]: https://source.denx.de/u-boot/u-boot/-/commit/c9507f07a1d6c92bd1f73fd64384f8c5994be9c2

Signed-off-by: Aniket Limaye <a-limaye@ti.com>
Signed-off-by: Ryan Eatmon <reatmon@ti.com>

meta-ti-bsp/conf/machine/j721e-sk-k3r5.conf

@@ -0,0 +1,11 @@
+#@TYPE: Machine
+#@NAME: J721e SK (R5F)
+#@DESCRIPTION: Machine configuration for the TI J721e SK (R5F core)
+
+require conf/machine/include/k3r5.inc
+
+SYSFW_SOC = "j721e"
+SYSFW_CONFIG = "evm"
+SYSFW_SUFFIX = "gp"
+
+UBOOT_MACHINE = "j721e_sk_r5_defconfig"

meta-ti-bsp/conf/machine/j721e-sk.conf

@@ -0,0 +1,16 @@
+#@TYPE: Machine
+#@NAME: J721e SK
+#@DESCRIPTION: Machine configuration for the TI J721e SK
+
+require conf/machine/include/j721e.inc
+
+KERNEL_DEVICETREE_PREFIX = " \
+    ti/k3-j721e-sk \
+    ti/k3-fpdlink \
+"
+
+KERNEL_DEVICETREE = " \
+    ti/k3-j721e-sk.dtb \
+"
+
+UBOOT_MACHINE = "j721e_sk_a72_config"