tint: Fix doxygen error.

Change-Id: Ibca03d2838aac894ccd46a6999f2d8ab745ed15b
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/97881
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>

src/tint/symbol.h

@@ -41,7 +41,7 @@ class Symbol {
 #if TINT_SYMBOL_STORE_DEBUG_NAME
     /// Constructor
     /// @param val the symbol value
-    /// @param program_id the identifier of the program that owns this Symbol
+    /// @param pid the identifier of the program that owns this Symbol
     /// @param debug_name name of symbols used only for debugging
     Symbol(uint32_t val, tint::ProgramID pid, std::string debug_name);
 #endif