Clang-Format: Allow empty functions to be single-line

For example

```
OIIOOutputDriver::~OIIOOutputDriver()
{
}
```

becomes

```
OIIOOutputDriver::~OIIOOutputDriver() {}
```

Saves quite some vertical space, which is especially handy for
constructors.

Pull Request: blender/blender#105594

source/blender/simulation/intern/implicit_eigen.cpp

@@ -76,9 +76,7 @@ class fVector : public Eigen::Vector3f {
  public:
   typedef float *ctype;
 
-  fVector()
-  {
-  }
+  fVector() {}
 
   fVector(const ctype &v)
   {
@@ -108,9 +106,7 @@ class fMatrix : public Eigen::Matrix3f {
  public:
   typedef float (*ctype)[3];
 
-  fMatrix()
-  {
-  }
+  fMatrix() {}
 
   fMatrix(const ctype &v)
   {
@@ -144,9 +140,7 @@ class lVector : public Eigen::VectorXf {
  public:
   typedef Eigen::VectorXf base_t;
 
-  lVector()
-  {
-  }
+  lVector() {}
 
   template<typename T> lVector &operator=(T rhs)
   {
@@ -177,9 +171,7 @@ typedef Eigen::SparseMatrix<Scalar> lMatrix;
  * matrix can be filled using construct().
  */
 struct lMatrixCtor {
-  lMatrixCtor()
-  {
-  }
+  lMatrixCtor() {}
 
   void reset()
   {