fix: some preprocessor branches fixed

example/kalman_filter/kalman.h

@@ -84,7 +84,7 @@ public:
   uncertainty_type uncertainty;
 };
 
-#if UNITS_COMP_CLANG <= 16
+#if UNITS_COMP_CLANG && UNITS_COMP_CLANG <= 16
 
 template<QuantityOrQuantityPoint QQP, units::Quantity U>
 estimation(state<QQP>, U) -> estimation<QQP>;

src/core/include/units/bits/external/hacks.h

@@ -94,7 +94,7 @@
 #include <compare>
 #include <concepts>
 
-#if UNITS_COMP_MSVC || UNITS_COMP_CLANG < 16
+#if UNITS_COMP_MSVC || (UNITS_COMP_CLANG && UNITS_COMP_CLANG < 16)
 
 #define TYPENAME typename
 
@@ -114,7 +114,7 @@
 
 #endif
 
-#if UNITS_COMP_MSVC || UNITS_COMP_GCC < 11
+#if UNITS_COMP_MSVC || (UNITS_COMP_GCC && UNITS_COMP_GCC < 11)
 
 #define UNITS_CONSTRAINED_NTTP_WORKAROUND(X)