hadrian: Pass -DNOSMP to C compiler when needed

Hadrian passes the -DNOSMP flag to GHC when the target doesn't support
SMP, but doesn't pass it to CC as well, leading to the following
compilation error on mips64el:

| Run Cc (FindCDependencies CDep) Stage1: rts/sm/NonMovingScav.c => _build/stage1/rts/build/c/sm/NonMovingScav.o.d
Command line: /usr/bin/mips64el-linux-gnuabi64-gcc -E -MM -MG -MF _build/stage1/rts/build/c/hooks/FlagDefaults.thr_debug_p_o.d -MT _build/stage1/rts/build/c/hooks/FlagDefaults.o -Irts/include -I_build/stage1/rts/build -I_build/stage1/rts/build/include -Irts/include -x c rts/hooks/FlagDefaults.c -Wall -Wextra -Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations -Winline -Wpointer-arith -Wmissing-noreturn -Wnested-externs -Wredundant-decls -Wundef -fno-strict-aliasing -DTHREADED_RTS -DDEBUG -fomit-frame-pointer -O2 -g -Irts -I_build/stage1/rts/build -DDEBUG -fno-omit-frame-pointer -g3 -O0
===> Command failed with error code: 1
In file included from rts/include/Stg.h:348,
                 from rts/include/Rts.h:38,
                 from rts/hooks/FlagDefaults.c:8:
rts/include/stg/SMP.h:416:2: error: #error memory barriers unimplemented on this architecture
  416 | #error memory barriers unimplemented on this architecture
      |  ^~~~~
rts/include/stg/SMP.h:440:2: error: #error memory barriers unimplemented on this architecture
  440 | #error memory barriers unimplemented on this architecture
      |  ^~~~~
rts/include/stg/SMP.h:464:2: error: #error memory barriers unimplemented on this architecture
  464 | #error memory barriers unimplemented on this architecture
      |  ^~~~~

The old make system correctly passed this flag to both GHC and CC [1].

Fix this error by passing -DNOSMP to CC as well.

[1] https://gitlab.haskell.org/ghc/ghc/-/blob/00920f176b0235d5bb52a8e054d89a664f8938fe/rts/ghc.mk#L407

Closes #24082

hadrian/src/Settings/Packages.hs

@@ -302,13 +302,11 @@ rtsPackageArgs = package rts ? do
     let ghcArgs = mconcat
           [ arg "-Irts"
           , arg $ "-I" ++ path
-          , notM targetSupportsSMP           ? arg "-DNOSMP"
           , way `elem` [debug, debugDynamic] ? pure [ "-DTICKY_TICKY"
                                                     , "-optc-DTICKY_TICKY"]
           , Profiling `wayUnit` way          ? arg "-DPROFILING"
           , Threaded  `wayUnit` way          ? arg "-DTHREADED_RTS"
-          , notM targetSupportsSMP           ? pure [ "-DNOSMP"
-                                                    , "-optc-DNOSMP" ]
+          , notM targetSupportsSMP           ? arg "-optc-DNOSMP"
           ]
 
     let cArgs = mconcat
@@ -326,6 +324,8 @@ rtsPackageArgs = package rts ? do
           , arg "-Irts"
           , arg $ "-I" ++ path
 
+          , notM targetSupportsSMP           ? arg "-DNOSMP"
+
           , Debug     `wayUnit` way          ? pure [ "-DDEBUG"
                                                     , "-fno-omit-frame-pointer"
                                                     , "-g3"