seabios-hppa: Update to SeaBIOS hppa version 1

Changes include:
* gcc-10 compile fix
* NetBSD boot fix due to wrong power button address
* Fix endian bug in romfile_loadint()
* Introduce SeaBIOS firmware version check
* Implement QEMU fw_cfg interface support

Required for proper version checking and gcc-10 update on Debian.

Signed-off-by: Helge Deller <deller@gmx.de>

seabios-hppa @ 4ff7639e

-Subproject commit 1630ac7d65c4a09218cc677f1fa56cd5b3140447
+Subproject commit 4ff7639e2b86d5775fa7d5cd0dbfa4d3a385a701