fix stack frame usage in Esirkepov solver

- old version used `float` to access a `floatD_X` array, this end in  stack frames usage
```
[0mptxas info    : Function properties for _ZN8picongpu20kernelComputeCurrentILi2EN5PMacc20SuperCellDescriptionINS1_4math2CT6VectorIN4mpl_10integral_cIiLi8EEES8_NS7_IiLi4EEEEENS4_3IntILi2ELi2ELi2EEENSB_ILi3ELi3ELi3EEEEELj3ENS1_7DataBoxINS1_10PitchedBoxINS3_6VectorIfLi3ENS3_16StandartAccessorENS3_17StandartNavigatorENS3_6detail17Vector_componentsEEELj3EEEEENS1_12ParticlesBoxINS1_5FrameINS1_15ParticlesBufferINS1_19ParticleDescriptionIN5boost3mpl6stringILi101ELi0ELi0ELi0ELi0ELi0ELi0ELi0EEESA_NSU_6v_itemINS_24placeholder_definition179weightingENSX_INS_24placeholder_definition158momentumENSX_INS_24placeholder_definition128positionINS_24placeholder_definition1412position_picENS1_24placeholder_definition1113pmacc_isAliasEEENSU_7vector0INS6_2naEEELi0EEELi0EEELi0EEENSU_6vectorINS_24placeholder_definition2114particlePusherINS_9particles6pusher5BorisES17_EENS_24placeholder_definition205shapeINS1I_6shapes3TSCES17_EENS_24placeholder_definition2213interpolationINS_28FieldToParticleInterpolationIS1P_NS_30AssignedTrilinearInterpolationEEES17_EENS_24placeholder_definition237currentINS_13currentSolver9EsirkepovIS1P_Lj3EEES17_EES1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_EENSX_INS_12MemoryFactorILm2EEENSX_INS_15CommunicationIdILj5EEES1B_Li0EEELi0EEEEESA_Lj3EE29OperatorCreatePairStaticArrayILj256EEENSS_ISW_SA_NSX_INS1_23placeholder_definition99multiMaskENSX_INS1_23placeholder_definition812localCellIdxES1E_Li0EEELi0EEES23_S29_EEEELj3EEENS1_13StrideMappingILj3ELj3ENS1_18MappingDescriptionILj3ESA_EEEENS_22ComputeCurrentPerFrameIS21_NS_8VelocityESA_EEEEvT2_T3_T5_T4_[0m
[0m    72 bytes stack frame, 0 bytes spill stores, 0 bytes spill loads[0m
[0mptxas info    : Used 64 registers, 18256 bytes smem, 496 bytes cmem[0], 24 bytes cmem[2][0m
```
- change `const float` index to `const uint32_t` to solve the problem
```
[0mptxas info    : Function properties for _ZN8picongpu20kernelComputeCurrentILi2EN5PMacc20SuperCellDescriptionINS1_4math2CT6VectorIN4mpl_10integral_cIiLi8EEES8_NS7_IiLi4EEEEENS4_3IntILi2ELi2ELi2EEENSB_ILi3ELi3ELi3EEEEELj3ENS1_7DataBoxINS1_10PitchedBoxINS3_6VectorIfLi3ENS3_16StandartAccessorENS3_17StandartNavigatorENS3_6detail17Vector_componentsEEELj3EEEEENS1_12ParticlesBoxINS1_5FrameINS1_15ParticlesBufferINS1_19ParticleDescriptionIN5boost3mpl6stringILi101ELi0ELi0ELi0ELi0ELi0ELi0ELi0EEESA_NSU_6v_itemINS_24placeholder_definition179weightingENSX_INS_24placeholder_definition158momentumENSX_INS_24placeholder_definition128positionINS_24placeholder_definition1412position_picENS1_24placeholder_definition1113pmacc_isAliasEEENSU_7vector0INS6_2naEEELi0EEELi0EEELi0EEENSU_6vectorINS_24placeholder_definition2114particlePusherINS_9particles6pusher5BorisES17_EENS_24placeholder_definition205shapeINS1I_6shapes3TSCES17_EENS_24placeholder_definition2213interpolationINS_28FieldToParticleInterpolationIS1P_NS_30AssignedTrilinearInterpolationEEES17_EENS_24placeholder_definition237currentINS_13currentSolver9EsirkepovIS1P_Lj3EEES17_EES1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_S1A_EENSX_INS_12MemoryFactorILm2EEENSX_INS_15CommunicationIdILj5EEES1B_Li0EEELi0EEEEESA_Lj3EE29OperatorCreatePairStaticArrayILj256EEENSS_ISW_SA_NSX_INS1_23placeholder_definition99multiMaskENSX_INS1_23placeholder_definition812localCellIdxES1E_Li0EEELi0EEES23_S29_EEEELj3EEENS1_13StrideMappingILj3ELj3ENS1_18MappingDescriptionILj3ESA_EEEENS_22ComputeCurrentPerFrameIS21_NS_8VelocityESA_EEEEvT2_T3_T5_T4_[0m
[0m    0 bytes stack frame, 0 bytes spill stores, 0 bytes spill loads[0m
[0mptxas info    : Used 60 registers, 18256 bytes smem, 496 bytes cmem[0], 24 bytes cmem[2][0m
```