doc: board: j721e_evm: Fix code-block type and indents

* BASH code should be labeled as such.
 * Code blocks should be indented by 4 spaces.

Fix these here.

Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/doc/board/ti/j721e_evm.rst b/doc/board/ti/j721e_evm.rst
index 8608373..ad70f15 100644
--- a/doc/board/ti/j721e_evm.rst
+++ b/doc/board/ti/j721e_evm.rst
@@ -154,37 +154,37 @@
 ----------------
 1. SYSFW:
 
-.. code-block:: text
+.. code-block:: bash
 
- $ make CROSS_COMPILE=arm-linux-gnueabihf- SOC=j721e
+    make CROSS_COMPILE=arm-linux-gnueabihf- SOC=j721e
 
 2. ATF:
 
-.. code-block:: text
+.. code-block:: bash
 
- $ make CROSS_COMPILE=aarch64-linux-gnu- ARCH=aarch64 PLAT=k3 TARGET_BOARD=generic SPD=opteed
+    make CROSS_COMPILE=aarch64-linux-gnu- ARCH=aarch64 PLAT=k3 TARGET_BOARD=generic SPD=opteed
 
 3. OPTEE:
 
-.. code-block:: text
+.. code-block:: bash
 
- $ make PLATFORM=k3-j721e CFG_ARM64_core=y
+    make PLATFORM=k3-j721e CFG_ARM64_core=y
 
 4. U-Boot:
 
 * 4.1 R5:
 
-.. code-block:: text
+.. code-block:: bash
 
- $ make CROSS_COMPILE=arm-linux-gnueabihf- j721e_evm_r5_defconfig O=build/r5
- $ make CROSS_COMPILE=arm-linux-gnueabihf- O=build/r5
+    make CROSS_COMPILE=arm-linux-gnueabihf- j721e_evm_r5_defconfig O=build/r5
+    make CROSS_COMPILE=arm-linux-gnueabihf- O=build/r5
 
 * 4.2 A72:
 
-.. code-block:: text
+.. code-block:: bash
 
- $ make CROSS_COMPILE=aarch64-linux-gnu- j721e_evm_a72_defconfig O=build/a72
- $ make CROSS_COMPILE=aarch64-linux-gnu- ATF=<ATF dir>/build/k3/generic/release/bl31.bin TEE=<OPTEE OS dir>/out/arm-plat-k3/core/tee-pager_v2.bin DM=<DM firmware>/ti-dm/j721e/ipc_echo_testb_mcu1_0_release_strip.xer5f O=build/a72
+    make CROSS_COMPILE=aarch64-linux-gnu- j721e_evm_a72_defconfig O=build/a72
+    make CROSS_COMPILE=aarch64-linux-gnu- ATF=<ATF dir>/build/k3/generic/release/bl31.bin TEE=<OPTEE OS dir>/out/arm-plat-k3/core/tee-pager_v2.bin DM=<DM firmware>/ti-dm/j721e/ipc_echo_testb_mcu1_0_release_strip.xer5f O=build/a72
 
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