moved sse implementation to sse folder

Rakefile

@@ -6,7 +6,7 @@ require 'rake/extensiontask'
 
 spec = Gem::Specification.load('digest-blake2b.gemspec')
 
-Rake::ExtensionTask.new('digest/blake2b/ext', spec) do |ext|
+Rake::ExtensionTask.new('digest/blake2b/sse', spec) do |ext|
   ext.source_pattern = '*.{c,h}'
 end
 

digest-blake2b.gemspec

@@ -41,7 +41,7 @@ Gem::Specification.new do |spec|
 
   spec.executables = spec.files.grep %r{^exe/}, &File.method(:basename)
 
-  spec.extensions << 'ext/digest/blake2b/ext/extconf.rb'
+  spec.extensions << 'ext/digest/blake2b/sse/extconf.rb'
 
   spec.add_development_dependency 'bundler'      , '~> 2.2'
   spec.add_development_dependency 'minitest'     , '~> 5.11'

ext/digest/blake2b/sse/extconf.rb

@@ -1,3 +1,3 @@
 require 'mkmf'
 $CFLAGS += ' -Wall -Wextra -std=c99 -pedantic -Wno-long-long'
-create_makefile 'digest/blake2b/ext'
+create_makefile 'digest/blake2b/sse'