Fix Woverflow warnings in PacketMathFP16

Eigen/src/Core/arch/AVX512/PacketMathFP16.h

diff --git a/Eigen/src/Core/arch/AVX512/PacketMathFP16.h b/Eigen/src/Core/arch/AVX512/PacketMathFP16.h
index 93ae95b..df5a0ef 100644
--- a/Eigen/src/Core/arch/AVX512/PacketMathFP16.h
+++ b/Eigen/src/Core/arch/AVX512/PacketMathFP16.h
@@ -260,7 +260,7 @@
 template <>

 EIGEN_STRONG_INLINE Packet32h pcmp_eq(const Packet32h& a, const Packet32h& b) {

   __mmask32 mask = _mm512_cmp_ph_mask(a, b, _CMP_EQ_OQ);

-  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi32(0), mask, 0xffffu));

+  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi32(0), mask, static_cast<short>(0xffffu)));

 }

 

 // pcmp_le

@@ -268,7 +268,7 @@
 template <>

 EIGEN_STRONG_INLINE Packet32h pcmp_le(const Packet32h& a, const Packet32h& b) {

   __mmask32 mask = _mm512_cmp_ph_mask(a, b, _CMP_LE_OQ);

-  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi32(0), mask, 0xffffu));

+  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi32(0), mask, static_cast<short>(0xffffu)));

 }

 

 // pcmp_lt

@@ -276,7 +276,7 @@
 template <>

 EIGEN_STRONG_INLINE Packet32h pcmp_lt(const Packet32h& a, const Packet32h& b) {

   __mmask32 mask = _mm512_cmp_ph_mask(a, b, _CMP_LT_OQ);

-  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi32(0), mask, 0xffffu));

+  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi32(0), mask, static_cast<short>(0xffffu)));

 }

 

 // pcmp_lt_or_nan

@@ -284,7 +284,7 @@
 template <>

 EIGEN_STRONG_INLINE Packet32h pcmp_lt_or_nan(const Packet32h& a, const Packet32h& b) {

   __mmask32 mask = _mm512_cmp_ph_mask(a, b, _CMP_NGE_UQ);

-  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi16(0), mask, 0xffffu));

+  return _mm512_castsi512_ph(_mm512_mask_set1_epi16(_mm512_set1_epi16(0), mask, static_cast<short>(0xffffu)));

 }

 

 // padd