Enable MaxMin tests for Float/Double on LoZ, and disable them on zOS

- Enables the Float & Double MaxMin tests on Linux on Z
- Disables them on z/OS, since TRIL parser cannot handle NaN values

Closes: #5157

Signed-off-by: Sarwat Shaheen <sarwat.shaheen@yahoo.com>

fvtest/compilertriltest/MaxMinTest.cpp

@@ -203,8 +203,7 @@ TEST_P(FloatMaxMin, UsingConst) {
     auto param = TRTest::to_struct(GetParam());
 
     if (std::isnan(param.lhs) || std::isnan(param.rhs)) {
-       SKIP_ON_S390(KnownBug) << "fmin / fmax returns wrong value for NaN on Z (see issue #5157)";
-       SKIP_ON_S390X(KnownBug) << "fmin / fmax returns wrong value for NaN on Z (see issue #5157)";
+       SKIP_ON_ZOS(KnownBug) << "fmin / fmax returns wrong value for NaN on Z (see issue #5157)";
     }
 
     char inputTrees[1024] = {0};
@@ -238,8 +237,7 @@ TEST_P(FloatMaxMin, UsingLoadParam) {
     auto param = TRTest::to_struct(GetParam());
 
     if (std::isnan(param.lhs) || std::isnan(param.rhs)) {
-       SKIP_ON_S390(KnownBug) << "fmin / fmax returns wrong value for NaN on Z (see issue #5157)";
-       SKIP_ON_S390X(KnownBug) << "fmin / fmax returns wrong value for NaN on Z (see issue #5157)";
+       SKIP_ON_ZOS(KnownBug) << "fmin / fmax returns wrong value for NaN on Z (see issue #5157)";
     }
 
     char inputTrees[1024] = {0};
@@ -281,8 +279,7 @@ TEST_P(DoubleMaxMin, UsingConst) {
     auto param = TRTest::to_struct(GetParam());
 
     if (std::isnan(param.lhs) || std::isnan(param.rhs)) {
-       SKIP_ON_S390(KnownBug) << "dmin / dmax returns wrong value for NaN on Z (see issue #5157)";
-       SKIP_ON_S390X(KnownBug) << "dmin / dmax returns wrong value for NaN on Z (see issue #5157)";
+       SKIP_ON_ZOS(KnownBug) << "dmin / dmax returns wrong value for NaN on Z (see issue #5157)";
     }
 
     char inputTrees[1024] = {0};
@@ -316,9 +313,7 @@ TEST_P(DoubleMaxMin, UsingLoadParam) {
     auto param = TRTest::to_struct(GetParam());
 
     if (std::isnan(param.lhs) || std::isnan(param.rhs)) {
-       SKIP_ON_S390(KnownBug) << "dmin / dmax returns wrong value for NaN on Z (see issue #5157)";
-       SKIP_ON_S390X(KnownBug) << "dmin / dmax returns wrong value for NaN on Z (see issue #5157)";
-
+       SKIP_ON_ZOS(KnownBug) << "dmin / dmax returns wrong value for NaN on Z (see issue #5157)";
     }
 
     char inputTrees[1024] = {0};