Switch transmute_ptr_to_ptr to "pedantic" class.

Per discussion in rust-lang/rust-clippy#6372, this lint has significant false positives.

Author: taralx

clippy_lints/src/lib.rs

@@ -1405,6 +1405,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(strings::STRING_ADD_ASSIGN),
         LintId::of(trait_bounds::TRAIT_DUPLICATION_IN_BOUNDS),
         LintId::of(trait_bounds::TYPE_REPETITION_IN_BOUNDS),
+        LintId::of(transmute::TRANSMUTE_PTR_TO_PTR),
         LintId::of(types::LINKEDLIST),
         LintId::of(types::OPTION_OPTION),
         LintId::of(unicode::NON_ASCII_LITERAL),
@@ -1693,7 +1694,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(transmute::TRANSMUTE_INT_TO_BOOL),
         LintId::of(transmute::TRANSMUTE_INT_TO_CHAR),
         LintId::of(transmute::TRANSMUTE_INT_TO_FLOAT),
-        LintId::of(transmute::TRANSMUTE_PTR_TO_PTR),
         LintId::of(transmute::TRANSMUTE_PTR_TO_REF),
         LintId::of(transmute::UNSOUND_COLLECTION_TRANSMUTE),
         LintId::of(transmute::WRONG_TRANSMUTE),
@@ -1927,7 +1927,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(transmute::TRANSMUTE_INT_TO_BOOL),
         LintId::of(transmute::TRANSMUTE_INT_TO_CHAR),
         LintId::of(transmute::TRANSMUTE_INT_TO_FLOAT),
-        LintId::of(transmute::TRANSMUTE_PTR_TO_PTR),
         LintId::of(transmute::TRANSMUTE_PTR_TO_REF),
         LintId::of(types::BORROWED_BOX),
         LintId::of(types::TYPE_COMPLEXITY),

clippy_lints/src/transmute/mod.rs

@@ -274,7 +274,7 @@ declare_clippy_lint! {
     /// let _ = unsafe{ &*(&1u32 as *const u32 as *const f32) };
     /// ```
     pub TRANSMUTE_PTR_TO_PTR,
-    complexity,
+    pedantic,
     "transmutes from a pointer to a pointer / a reference to a reference"
 }