Remove wrong enum explanation

Author: DiegoCivi

docs/gas_builtin_accounting.md

@@ -174,7 +174,7 @@ This information is NOT used for the gas calculation, as the gas cost of
 builtins is already taken into account during the [gas accounting process](./gas.md).
 The builtins counter types can each be found in the [types folder](../src/types/).
 Taking the [Pedersen hash](../src/types/pedersen.rs) as an example, we see
-that the counters will be represented as i64 integers in MLIR.
+that the counters will be represented as `i64` integers in MLIR.
 Counters are then simply incremented by one each time the builtins are
 called from within the program.
 

docs/overview.md

@@ -119,17 +119,6 @@ Path: `src/libfuncs`
 Here are stored all the library function implementations in MLIR, this
 contains the majority of the code.
 
-To store information about the different types of library functions sierra
-has, we divide them into the following using the enum `SierraLibFunc`:
-
-- **Branching**: These functions are implemented inline, adding blocks and
-  jumping as necessary based on given conditions.
-- **Constant**: A constant value, this isn't represented as a function and
-  is inserted inline.
-- **Function**: Any other function.
-- **InlineDataFlow**: Functions that can be implemented inline without much
-  problem. For example: `dup`, `store_temp`
-
 ### Statements
 
 Path: `src/statements`