[SeaBIOS] ACPI OEM Table ID length

Hi folks,

I ran into this problem while building Xen. unfortunately, I have
trouble building the same files with seabios git, and have even more
limited ability to test the changes.

Apparently ACPI says that the OEM Table Id must be length 8. Some of the
tables in seabios use longer. newer iASL rejects this and fails to
build the code. Most likely things handle it as if it was truncated, but
perhaps it overran to the next field.

I've used this diff, for your consideration.

diff --git a/src/fw/ssdt-misc.dsl b/src/fw/ssdt-misc.dsl
index acc850e..d1d2c9e 100644
--- a/src/fw/ssdt-misc.dsl
+++ b/src/fw/ssdt-misc.dsl
@@ -1,6 +1,6 @@
 ACPI_EXTRACT_ALL_CODE ssdp_misc_aml

-DefinitionBlock ("ssdt-misc.aml", "SSDT", 0x01, "BXPC", "BXSSDTSUSP", 0x1)
+DefinitionBlock ("ssdt-misc.aml", "SSDT", 0x01, "BXPC", "BXSSDTSU", 0x1)
 {

/****************************************************************
diff --git a/src/fw/ssdt-pcihp.dsl b/src/fw/ssdt-pcihp.dsl
index cb24c11..518a5eb 100644
--- a/src/fw/ssdt-pcihp.dsl
+++ b/src/fw/ssdt-pcihp.dsl
@@ -1,6 +1,6 @@
 ACPI_EXTRACT_ALL_CODE ssdp_pcihp_aml

-DefinitionBlock ("ssdt-pcihp.aml", "SSDT", 0x01, "BXPC", "BXSSDTPCIHP", 0x1)
+DefinitionBlock ("ssdt-pcihp.aml", "SSDT", 0x01, "BXPC", "BXSSDTPC", 0x1)
 {

/****************************************************************