rcutil: directly call win32.executablepath()

Since it isn't supported on POSIX platform, we don't need to double the
compatibility layers.

mercurial/posix.py

@@ -626,9 +626,6 b' class cachestat(object):'
     def __ne__(self, other):
         return not self == other
 
-def executablepath():
-    return None # available on Windows only
-
 def statislink(st):
     '''check whether a stat result is a symlink'''
     return st and stat.S_ISLNK(st.st_mode)

mercurial/scmwindows.py

@@ -21,7 +21,7 b" fallbackpager = 'more'"
 def systemrcpath():
     '''return default os-specific hgrc search path'''
     rcpath = []
-    filename = util.executablepath()
+    filename = win32.executablepath()
     # Use mercurial.ini found in directory with hg.exe
     progrc = os.path.join(os.path.dirname(filename), 'mercurial.ini')
     rcpath.append(progrc)

mercurial/util.py

@@ -108,7 +108,6 b' cachestat = platform.cachestat'
 checkexec = platform.checkexec
 checklink = platform.checklink
 copymode = platform.copymode
-executablepath = platform.executablepath
 expandglobs = platform.expandglobs
 explainexit = platform.explainexit
 findexe = platform.findexe

mercurial/windows.py

@@ -31,7 +31,6 b' except ImportError:'
 
 osutil = policy.importmod(r'osutil')
 
-executablepath = win32.executablepath
 getfsmountpoint = win32.getvolumename
 getfstype = win32.getfstype
 getuser = win32.getuser