Support reserved [0-100] and non-reserved[101-65535] Clang/GNU init priority values on AIX.
This patch maps Clang/GNU values into priority values used in sinit/sterm functions. User can play with values and be able to get init to occur before or after XL init and vice versa.
The conversion strategies are: For [0-100] reserved and [101-65535] non-reserved Clang/GNU values, we use linear interpolation to map Clang to sinit/sterm priority values. But 21/20 on reserved range ends and 1024 on both non-reserved range ends will be used with a factor of 1.