SecurityPkg: Create library for enrolling Secure Boot variables.

This commits add library, which consist functions to
enrolll Secure Boot keys and initialize Secure Boot
default variables. Some of the functions was moved
 from SecureBootConfigImpl.c file.

Signed-off-by: Grzegorz Bernacki <gjb@semihalf.com>
Reviewed-by: Sunny Wang <sunny.wang@arm.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>

SecurityPkg/SecurityPkg.dec

@@ -91,6 +91,10 @@
   ## @libraryclass  Provides helper functions related to creation/removal Secure Boot variables.
   #
   SecureBootVariableLib|Include/Library/SecureBootVariableLib.h
+
+  ## @libraryclass  Provides support to enroll Secure Boot keys.
+  #
+  SecureBootVariableProvisionLib|Include/Library/SecureBootVariableProvisionLib.h
 [Guids]
   ## Security package token space guid.
   # Include/Guid/SecurityPkgTokenSpace.h