Clean up E0466 explanation

diff --git a/src/librustc_error_codes/error_codes/E0466.md b/src/librustc_error_codes/error_codes/E0466.md
index 443b7bae1345e5fdae42cf0787b63137bf73a2e6..7aefedbc0875d7dc7412e3b11c25684beb89c96a 100644 (file)
--- a/src/librustc_error_codes/error_codes/E0466.md
+++ b/src/librustc_error_codes/error_codes/E0466.md
@@ -1,4 +1,4 @@
-Macro import declarations were malformed.
+Macro import declaration was malformed.
 
 Erroneous code examples: