[NTOS:PS] Implement PS_QUOTA_TYPE and let the quota code use it (#3389)

[NTOS:PS] Implement PS_QUOTA_TYPE and let the quota code use it (#3389)

This will replace the PoolIndex variable and as such we'll only be using the PS_QUOTA_TYPE enumeration, as Windows does. Both QuotaEntry, QuotaUsage and QuotaPeak depend explicitly or implicitly on this enumeration. Further details about this enum can be found in the following articles.
https://www.geoffchappell.com/studies/windows/km/ntoskrnl/api/ps/psquota/type.htm?tx=68,143
https://www.geoffchappell.com/studies/windows/km/ntoskrnl/api/ps/psquota/block.htm?tx=68,142,143
https://www.geoffchappell.com/studies/windows/km/ntoskrnl/inc/ps/eprocess/index.htm (see QuotaPeak and QuotaUsage)