Remove duplicative constants in state.go and fix mismatched page size

[mininny]

There are two different constant definition in state.go and memory.go which are confusing and actually mis-used. This PR removes the constant definition in state.go and fix the call in memory.go/GetUnaligned.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 61.89%. Comparing base (8ff9318) to head (056f92e).

Files with missing lines	Patch %	Lines
rvgo/fast/memory.go	50.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #104   +/-   ##
=======================================
  Coverage   61.89%   61.89%           
=======================================
  Files          27       27           
  Lines        4091     4091           
=======================================
  Hits         2532     2532           
  Misses       1427     1427           
  Partials      132      132           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.