Basic string intrinsics for Sparc

We need to adapt the following string related intrinsics on Sparc to compact strings:
- String.equals
- String.compareTo
- StringCoderLatin1.toBytes0 (inline_string_copy(true), StrCompressedCopy, string_compress)
- StringCoderLatin1.toChars0 (inline_string_copy(false), StrInflatedCopy, string_inflate)

We currently don't have an intrinsic for String.indexOf. We may add it later if performance results suggest that we need it with compressed strings.