misc: Fix coding style for union's opening braces

The systemc dir was not included in this fix.

First it was identified that there were only occurrences
at 0, 1, 2 and 3 levels of indentation, using:

    grep -nrE --exclude-dir=systemc \
        "^ *union [A-Za-z].* {$" src/

Then the following commands were run to replace:

    <indent level>union X ... {

by:

    <indent level>union X ...
    <indent level>{

Level 0:
    grep -nrl --exclude-dir=systemc \
        "^union [A-Za-z].* {$" src/ | \
        xargs sed -Ei \
        's/^union ([A-Za-z].*) \{$/union \1\n\{/g'

Level 1:
    grep -nrl --exclude-dir=systemc \
        "^    union [A-Za-z].* {$" src/ | \
        xargs sed -Ei \
        's/^    union ([A-Za-z].*) \{$/    union \1\n    \{/g'

and so on.

Change-Id: I066854eb27a8acd2cc2dfa41596bb1b1f66c71b1
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/43328
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Gabe Black <gabe.black@gmail.com>

src/cpu/inst_res.hh

@@ -46,7 +46,8 @@
 class InstResult
 {
   public:
-    union MultiResult {
+    union MultiResult
+    {
         uint64_t integer;
         double dbl;
         TheISA::VecRegContainer vector;