If you have a second, identical working board, you can use an external programmer to "read" the chip and save it as a .bin to flash onto the broken board. How to Flash the BIOS Binary
If you cannot find a direct .bin download, you can generate one from the official update file: Extract Bios BIN file from EXE file nutmeg-mini-itx rev 1.0 bios bin file
HP usually provides BIOS updates as .exe files. You can often extract the raw .bin or .rom image yourself: : Visit the HP Software and Driver Downloads page and enter your specific PC model (e.g., HP 110-503a Go to product viewer dialog for this item. If you have a second, identical working board,
Looking for the manual for the Nutmeg Mini-ITX with J2900 SoC If you have a second