arch-riscv: Remove spaces around ea_code

This patch makes mem.isa conform to style guidelines better by removing
spaces around the "ea_code" argument default value assignment of the
Load format.

Change-Id: I1c62b99de3617a3734b128b00fb421773e021317
Reviewed-on: https://gem5-review.googlesource.com/6181
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Alec Roelke <ar4jc@virginia.edu>

src/arch/riscv/isa/formats/mem.isa

@@ -254,7 +254,7 @@ def template StoreCompleteAcc {{
     }
 }};
 
-def format Load(memacc_code, ea_code = {{EA = Rs1 + offset;}}, mem_flags=[],
+def format Load(memacc_code, ea_code={{EA = Rs1 + offset;}}, mem_flags=[],
         inst_flags=[]) {{
     offset_code = """
                     offset = IMM12;