ti-dm: Update firmware to 08.04.01.08

Update the following ti-dm firmware
08.04.01.08 for AM62x

Major changes compared to previous version:
- Switched to ipc echo test application to enable A53 <-> DM R5 IPC
- Switched to latest sitara PDK baseline

MD5 Checksum:
ec872a8f6e008b42cd4ab620dd6e6df4  ti-dm/am62xx/ipc_echo_testb_mcu1_0_release_strip.xer5f

Signed-off-by: Vishal Mahaveer <vishalm@ti.com>
Signed-off-by: Devarsh Thakkar <devarsht@ti.com>
Signed-off-by: Praneeth Bajjuri <praneeth@ti.com>