Upgrade to rust 1.39.0 (#6939)

* Upgrade to rust 1.39.0

* 1.39.0 clippy

sdk/src/entrypoint.rs

@@ -38,6 +38,8 @@ macro_rules! entrypoint {
 }
 
 /// Deserialize the input parameters
+///
+/// # Safety
 #[allow(clippy::type_complexity)]
 pub unsafe fn deserialize<'a>(input: *mut u8) -> (&'a Pubkey, Vec<AccountInfo<'a>>, &'a [u8]) {
     let mut offset: usize = 0;

sdk/src/instruction_processor_utils.rs

@@ -41,7 +41,7 @@ pub fn next_keyed_account<I: Iterator>(iter: &mut I) -> Result<I::Item, Instruct
     iter.next().ok_or(InstructionError::NotEnoughAccountKeys)
 }
 
-pub fn limited_deserialize<T>(data: &[u8]) -> Result<(T), InstructionError>
+pub fn limited_deserialize<T>(data: &[u8]) -> Result<T, InstructionError>
 where
     T: serde::de::DeserializeOwned,
 {