Correct - Extend msys search to all possible drives

Corrected version - Previously, the code was only checking for the msys installation in the C drive. This commit extends the search to all possible drives on the system. It generates all possible paths by combining each drive letter with each possible path, and then checks each one. This ensures that the msys installation can be found regardless of the drive it's installed on.
I proposed a change for a mid file by mistake, this one is working fine with a different drive letter.

gvsbuild/utils/builder.py

@@ -32,6 +32,7 @@
 from typing import Optional
 from urllib.error import ContentTooShortError, URLError
 from urllib.request import urlopen
+from string import ascii_uppercase
 
 from .base_expanders import dirlist2set, make_zip
 from .base_project import Project
@@ -230,13 +231,12 @@ def __check_tools(self, opts):
         log.start("Checking msys tool")
         msys_path = opts.msys_dir
         if not msys_path or not Path.exists(msys_path):
-            msys_paths = [
-                Path(r"C:\msys64"),
-                Path(r"C:\msys32"),
-                Path(r"C:\tools\msys64"),
-                Path(r"C:\tools\msys32"),
-            ]
-            for path in msys_paths:
+            # list of drive letters to check
+            possible_drives = ['%s:' % d for d in ascii_uppercase if os.path.exists('%s:' % d)]
+            possible_paths = [r"\msys64", r"\tools\msys64", r"\msys32", r"\tools\msys32"]
+            all_possible_paths = [Path(drive + path) for drive in possible_drives for path in possible_paths]
+
+            for path in all_possible_paths:
                 if Path.exists(path):
                     msys_path = path
                     self.opts.msys_dir = str(msys_path)