Revert "add a .clang-format file (#9154)" (#9172)

I thought git would be smart enough to understand all the whitespace changes but even with all the flags I know to make it ignore theses it still blows up if there are identical changes on both sides.

I have a solution but it require creating a new commit at the merge base for each conflicting PR and merging it into develop.

I don't think blowing up all PRs is worth for now, maybe if we can coordinate this for V3 let's say.

This reverts commit 0d11331d18.

src/platform/nrf52/BLEDfuSecure.h

@@ -41,14 +41,15 @@
 #include "BLECharacteristic.h"
 #include "BLEService.h"
 
-class BLEDfuSecure : public BLEService {
-protected:
-  BLECharacteristic _chr_control;
+class BLEDfuSecure : public BLEService
+{
+  protected:
+    BLECharacteristic _chr_control;
 
-public:
-  BLEDfuSecure(void);
+  public:
+    BLEDfuSecure(void);
 
-  virtual err_t begin(void);
+    virtual err_t begin(void);
 };
 
 #endif /* BLEDFUSECURE_H_ */