COMPMID-1820: (Nightly) NEON/DepthConvertLayer/F16_to_F32 fails

-Removes shift from depth conversion tests.
-Changes Cast tolerance between float conversions to zero

Change-Id: I6c456f7d910eb3c02069f1e4d5df7b257d6d784e
Reviewed-on: https://review.mlplatform.org/341
Reviewed-by: Anthony Barbier <Anthony.barbier@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
diff --git a/tests/validation/CL/Cast.cpp b/tests/validation/CL/Cast.cpp
index 107edcd..854290d 100644
--- a/tests/validation/CL/Cast.cpp
+++ b/tests/validation/CL/Cast.cpp
@@ -226,7 +226,7 @@
 CAST_SUITE(F16_to_S16, DataType::F16, DataType::S16, CLCastToS16Fixture<half>, CastF16toS16Dataset, one_tolerance)
 CAST_SUITE(F16_to_U32, DataType::F16, DataType::U32, CLCastToU32Fixture<half>, CastF16toU32Dataset, one_tolerance)
 CAST_SUITE(F16_to_S32, DataType::F16, DataType::S32, CLCastToS32Fixture<half>, CastF16toS32Dataset, one_tolerance)
-CAST_SUITE(F16_to_F32, DataType::F16, DataType::F32, CLCastToF32Fixture<half>, CastF16toF32Dataset, one_tolerance)
+CAST_SUITE(F16_to_F32, DataType::F16, DataType::F32, CLCastToF32Fixture<half>, CastF16toF32Dataset, zero_tolerance)
 
 // F32
 CAST_SUITE(F32_to_U8, DataType::F32, DataType::U8, CLCastToU8Fixture<float>, CastF32toU8Dataset, one_tolerance)
@@ -235,7 +235,7 @@
 CAST_SUITE(F32_to_S16, DataType::F32, DataType::S16, CLCastToS16Fixture<float>, CastF32toS16Dataset, one_tolerance)
 CAST_SUITE(F32_to_U32, DataType::F32, DataType::U32, CLCastToU32Fixture<float>, CastF32toU32Dataset, one_tolerance)
 CAST_SUITE(F32_to_S32, DataType::F32, DataType::S32, CLCastToS32Fixture<float>, CastF32toS32Dataset, one_tolerance)
-CAST_SUITE(F32_to_F16, DataType::F32, DataType::F16, CLCastToF16Fixture<float>, CastF32toF16Dataset, one_tolerance)
+CAST_SUITE(F32_to_F16, DataType::F32, DataType::F16, CLCastToF16Fixture<float>, CastF32toF16Dataset, zero_tolerance)
 
 TEST_SUITE_END() // Cast
 TEST_SUITE_END() // CL