clangformat: don't noisily print status messages for every checked file

The version lookup should be silent. While we're at it, the version
lookup should not be happening more than once, which printing multiple
messages indicated we were doing. Pass the version into the per-file
function rather than looking it up fresh each time.

Fixes #11054 (comment)

mesonbuild/scripts/clangformat.py

@@ -23,10 +23,9 @@
 from ..programs import ExternalProgram
 import typing as T
 
-def run_clang_format(fname: Path, exelist: T.List[str], check: bool) -> subprocess.CompletedProcess:
+def run_clang_format(fname: Path, exelist: T.List[str], check: bool, cformat_ver: T.Optional[str]) -> subprocess.CompletedProcess:
     clangformat_10 = False
-    if check:
-        cformat_ver = ExternalProgram('clang-format', exelist).get_version()
+    if check and cformat_ver:
         if version_compare(cformat_ver, '>=10'):
             clangformat_10 = True
             exelist = exelist + ['--dry-run', '--Werror']
@@ -58,4 +57,9 @@ def run(args: T.List[str]) -> int:
         print('Could not execute clang-format "%s"' % ' '.join(exelist))
         return 1
 
-    return run_tool('clang-format', srcdir, builddir, run_clang_format, exelist, options.check)
+    if options.check:
+        cformat_ver = ExternalProgram('clang-format', exelist, silent=True).get_version()
+    else:
+        cformat_ver = None
+
+    return run_tool('clang-format', srcdir, builddir, run_clang_format, exelist, options.check, cformat_ver)