Fix cmake dependency on wasm-intrinsics.wat (WebAssembly#6206)

I think this is a nicer/better way to do WebAssembly#6204.

src/passes/CMakeLists.txt

@@ -1,19 +1,12 @@
 file(READ wasm-intrinsics.wat WASM_INTRINSICS_WAT HEX)
+set(CMAKE_CONFIGURE_DEPENDS wasm-intrinsics.wat)
 
 string(REGEX MATCHALL "([A-Fa-f0-9][A-Fa-f0-9])" SEPARATED_HEX ${WASM_INTRINSICS_WAT})
 
-# WASM_INTRINSICS_EMBED_2 and WASM_INTRINSICS_SIZE_2 should be renamed each time
-# the content of the wat file changes. This is not strictly necessary, as CMake
-# should use the fresh contents each time, but even just re-running CMake
-# manually is not enough in practice (one needs to also erase the CMake temp
-# files, or use a fresh build dir). Renaming the vars keeps things working
-# smoothly for people with existing checkouts.
-set(WASM_INTRINSICS_SIZE_2 1)
 foreach (hex IN LISTS SEPARATED_HEX)
-  string(APPEND WASM_INTRINSICS_EMBED_2 "0x${hex},")
-  math(EXPR WASM_INTRINSICS_SIZE_2 "${WASM_INTRINSICS_SIZE_2}+1")
+  string(APPEND WASM_INTRINSICS_EMBED "0x${hex},")
 endforeach ()
-string(APPEND WASM_INTRINSICS_EMBED_2 "0x00")
+string(APPEND WASM_INTRINSICS_EMBED "0x00")
 
 configure_file(WasmIntrinsics.cpp.in WasmIntrinsics.cpp @ONLY)
 

src/passes/WasmIntrinsics.cpp.in

@@ -1,7 +1,7 @@
 #include "passes/intrinsics-module.h"
 
-static const char theModule[@WASM_INTRINSICS_SIZE_2@] = {
-@WASM_INTRINSICS_EMBED_2@
+static const char theModule[] = {
+@WASM_INTRINSICS_EMBED@
 };
 
 namespace wasm {