[libcalamares] Provide overload of runCommand()

- Most of the time the working dir and stdin are not important,
   you just want to run a command in the host, so simplify that
   by providing a suitable overload.
 - Use that overload from the partition service (for mount and sync).

src/libcalamares/partition/Mount.cpp

@@ -69,8 +69,7 @@ mount( const QString& devicePath, const QString& mountPoint, const QString& file
         args << "-o" << options;
     }
 
-    auto r = CalamaresUtils::System::instance()->runCommand(
-        CalamaresUtils::System::RunLocation::RunInHost, args, QString(), QString(), 10 );
+    auto r = CalamaresUtils::System::instance()->runCommand( args, 10 );
     sync();
     return r.getExitCode();
 }

src/libcalamares/partition/Sync.cpp

@@ -23,14 +23,7 @@
 
 void CalamaresUtils::Partition::sync()
 {
-    auto* s = CalamaresUtils::System::instance();
-
-    auto r = s->runCommand( CalamaresUtils::System::RunLocation::RunInHost,
-                   { "/sbin/udevadm", "settle" },
-                   QString(),
-                   QString(),
-                   10 // timeout seconds
-    );
+    auto r = CalamaresUtils::System::runCommand( { "/sbin/udevadm", "settle" }, 10 );
 
     if ( r.getExitCode() != 0 )
     {
@@ -38,10 +31,5 @@ void CalamaresUtils::Partition::sync()
         r.explainProcess( "udevadm", 10 );
     }
 
-    s->runCommand( CalamaresUtils::System::RunLocation::RunInHost,
-                   { "/bin/sync" },
-                   QString(),
-                   QString(),
-                   10 // timeout seconds
-    );
+    CalamaresUtils::System::runCommand( { "/bin/sync" }, 10 );
 }

src/libcalamares/utils/CalamaresUtilsSystem.h

@@ -123,6 +123,18 @@ public:
         const QString& stdInput = QString(),
         int timeoutSec = 0 );
 
+    /** @brief Convenience wrapper for runCommand()
+     *
+     * Runs the given command-line @p args in the host in the current direcory
+     * with no input, and the given @p timeoutSec for completion.
+     */
+    static inline ProcessResult runCommand(
+        const QStringList& args,
+        int timeoutSec )
+    {
+        return runCommand( RunLocation::RunInHost, args, QString(), QString(), timeoutSec );
+    }
+
     /** @brief Convenience wrapper for runCommand().
      *  Runs the command in the location specified through the boolean
      *  doChroot(), which is what you usually want for running commands