msi: Properly check for a specified flag combination

[Andrew Talbot]

Changelog:
    msi: Properly check for a specified flag combination.

diff --git a/dlls/msi/action.c b/dlls/msi/action.c
index 62d857a..da76d4d 100644
--- a/dlls/msi/action.c
+++ b/dlls/msi/action.c
@@ -6441,7 +6441,7 @@ static UINT ACTION_RemoveODBC( MSIPACKAGE *package )
 #define ENV_MOD_PREFIX      0x80000000
 #define ENV_MOD_MASK        0xC0000000
 
-#define check_flag_combo(x, y) ((x) & ~(y)) == (y)
+#define check_flag_combo(x, y) ((x) & (y)) == (y)
 
 static UINT env_parse_flags( LPCWSTR *name, LPCWSTR *value, DWORD *flags )
 {