[QNN EP]Fix issue in LeakyRelu Opbuilder for HTP backend. (#15356)
### Description
Fix issue in LeakyRelu Opbuilder for HTP backend.
Qnn Prelu(Onnx LeakyRelu) requires alpha data as the 2nd input while
Onnx set it as attribute. HTP backend requires input to be quantized. It
caused Qnn Op validation failed by setting the 2ns input as float32 data
type.
Fix:
Need to set the 2nd input as quantized input for HTP backend. Calculate
the quantization parameter and quantize the alpha data into uint8.
### Motivation and Context
Unblock models with the LeakyRelu execution on QualComm HTP backend.