pc99, ltimer: Downgrade expected errors to warning

- If the ACPI isn't present don't try and parse HPET info.
- Don't print an error in function used to check if acpi tables are
accessible.

platsupport: use ZF_LOG* instead of custom macros

This commit removes redundant definitions of debug print macros
and replaces them with use of ZF_LOG*.

libplatsupport: Moved BIOS RSDP Parsing

Moved the parsing of the RSDP from BIOS to be handled at an
earlier step in the acpi initialisation procedure. Exported
the acpi_parse_table function from the walker code to parse
the rsdp table when initialising the acpi_t object.

libplatsupport: Modifications to RSDP parsing

Moved the parsing of the RSDP out of the table parsing procedure,
(_acpi_parse_tables). If the RSDP is not provided for ACPI
initialization, it will be searched for in the BIOS segment.
Modified the acpi_t struct to store the whole
RSDP object rather than the physical address of the object.

libplatsupport: Code style fixes (RSDP changes)

Small coding style fixes e.g fprintf to ZF_LOG, pointer
declaration.

libplatsupport: Initialize ACPI with given RSDP

Enable ACPI initialization by passing an RSDP object rather
than searching for it within the BIOS section. Updated default
logical timer initialization to initialize the ACPI with a given
RSDP object.

Fix whitespace

- remove trailing whitespace
- remove duplicate blank lines
- remove blank lines at end of file

fix licenses

acpi: use singleton to avoid parsing tables twice

Remove trailing whitespace

libplatsupport: Squash some compiler warnings.

libplatsupport: Fix various 32-bit assumptions

libplatsupport: Avoid shadowing variables.

This change has no effect on functionality, but helps poor users such as myself
who switch on -Wshadow, only to be buffeted with spurious warnings.