Suppress clang-tidy warning for C++20

clang-tidy-11 -p=build-clang src/ExternalSensor.cpp
./src/ExternalSensor.cpp:148:29: error: use nullptr [modernize-use-nullptr,-warnings-as-errors]
    return (ageElapsed(now) < writeTimeout);
                            ^
                            nullptr

clang-tidy-11 -p=build-clang src/CPUSensorMain.cpp
./src/CPUSensorMain.cpp:80:22: error: use nullptr [modernize-use-nullptr,-warnings-as-errors]
        return (name < rhs.name);
                     ^
                     nullptr

These are false positives fixed by:

https://reviews.llvm.org/D95714?id=320393

For now, suppress the lint.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: Ie839608819681476ba3c22201aeaaba7c22e4c05
diff --git a/src/CPUSensorMain.cpp b/src/CPUSensorMain.cpp
index 6106bc0..b36e6ad 100644
--- a/src/CPUSensorMain.cpp
+++ b/src/CPUSensorMain.cpp
@@ -77,6 +77,7 @@
 
     bool operator<(const CPUConfig& rhs) const
     {
+        // NOLINTNEXTLINE
         return (name < rhs.name);
     }
 };
diff --git a/src/ExternalSensor.cpp b/src/ExternalSensor.cpp
index 91f488b..22f5058 100644
--- a/src/ExternalSensor.cpp
+++ b/src/ExternalSensor.cpp
@@ -145,6 +145,7 @@
     }
 
     // If age, as of now, is less than timeout, it is deemed fresh
+    // NOLINTNEXTLINE
     return (ageElapsed(now) < writeTimeout);
 }