(*)Add parentheses in end_value_h4 for FMAs

  Added parentheses to prevent FMAs in 4 expressions in end_value_h4 that rely
on exact vertical symmetry in order to get the cancellations that are necessary
to pass the vertical remapping unit testing.  Before this change, the MOM6
unit-testing was failing when FMAs are enabled, but with it the unit-testing is
passing even when FMAs are enabled.  All answers are bitwise identical in cases
without FMAs, but answers could change with FMAs.

src/ALE/regrid_edge_values.F90

@@ -748,10 +748,10 @@ subroutine end_value_h4(dz, u, Csys)
   Wt(2,4) = -4.0 * I_h1234 * (I_h23 * (I_h123 + I_h234))             ! Wt*h1^3 > -4* (h1/h23)*(1+h1/h234)
   Wt(3,4) =  4.0 * I_denom  ! = 4.0*I_h1234 * I_h234 * I_h34         ! Wt*h1^3 < 4 * (h1/h234)*(h1/h34)
 
-  Csys(1) = ((u(1) + Wt(1,1) * (u(2)-u(1))) + Wt(2,1) * (u(3)-u(2))) + Wt(3,1) * (u(4)-u(3))
-  Csys(2) = (Wt(1,2) * (u(2)-u(1)) + Wt(2,2) * (u(3)-u(2))) + Wt(3,2) * (u(4)-u(3))
-  Csys(3) = (Wt(1,3) * (u(2)-u(1)) + Wt(2,3) * (u(3)-u(2))) + Wt(3,3) * (u(4)-u(3))
-  Csys(4) = (Wt(1,4) * (u(2)-u(1)) + Wt(2,4) * (u(3)-u(2))) + Wt(3,4) * (u(4)-u(3))
+  Csys(1) = ((u(1) + (Wt(1,1) * (u(2)-u(1)))) + (Wt(2,1) * (u(3)-u(2)))) + (Wt(3,1) * (u(4)-u(3)))
+  Csys(2) = ((Wt(1,2) * (u(2)-u(1))) + (Wt(2,2) * (u(3)-u(2)))) + (Wt(3,2) * (u(4)-u(3)))
+  Csys(3) = ((Wt(1,3) * (u(2)-u(1))) + (Wt(2,3) * (u(3)-u(2)))) + (Wt(3,3) * (u(4)-u(3)))
+  Csys(4) = ((Wt(1,4) * (u(2)-u(1))) + (Wt(2,4) * (u(3)-u(2)))) + (Wt(3,4) * (u(4)-u(3)))
 
   ! endif ! End of non-uniform layer thickness branch.