helpers.chh/h: add some helper functions

Partial cherry pick from:
https://bitbucket.org/neutrino-images/ni-neutrino-hd

Signed-off-by: Thilo Graf <dbt@novatux.de>


Origin commit data
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Branch: ni/coolstream
Commit: 43c7e0ed09
Author: vanhofen <vanhofen@gmx.de>
Date: 2016-08-11 (Thu, 11 Aug 2016)



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This commit was generated by Migit

src/system/helpers.h

@@ -146,4 +146,9 @@ std::string getJFFS2MountPoint(int mtdPos);
 std::string Lang2ISO639_1(std::string& lang);
 std::string readLink(std::string lnk);
 
+int getpidof(const char *process);
+std::string filehash(const char * file);
+std::string get_path(const char * path);
+inline bool file_exists(const std::string file) { return file_exists(file.c_str()); }
+
 #endif