NVMeSensorMain: Fix clang-tidy readability-else-after-return issue

clang-tidy-11 -p=build-clang src/NVMeSensorMain.cpp
../src/NVMeSensorMain.cpp:178:17: error: do not use 'else' after 'return' [readability-else-after-return,-warnings-as-errors]
                else if (ec)
                ^~~~~~~~~~~~

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: Iefcae04c641d350918e80d50f5addeb3160fa50f
diff --git a/src/NVMeSensorMain.cpp b/src/NVMeSensorMain.cpp
index d5a8c6b..49475fc 100644
--- a/src/NVMeSensorMain.cpp
+++ b/src/NVMeSensorMain.cpp
@@ -169,7 +169,8 @@
                 {
                     return; // we're being canceled
                 }
-                else if (ec)
+
+                if (ec)
                 {
                     std::cerr << "Error: " << ec.message() << "\n";
                     return;