Fix parantheses on return and sizeof statements.

Used script:
```
import re
import sys

for arg in sys.argv[1:]:
    print(arg)
    with open(arg, 'r') as file:
        content = file.read()
        content = re.sub(r"return\s?\((?!.*\).*\()\s*\n?(.*)\n?\);", r"return \1;", \
            content, flags = re.M)
        content = re.sub(r"sizeof ([^\(][a-zA-Z0-9_\[\]]*)", r"sizeof(\1)",\
            content, flags = re.M)
    with open(arg, 'w') as file:
        file.write(content)

```
Executed with:
` find . -regextype posix-egrep -regex ".*\.([hc]|fmt|function)" | xargs -L1 python script.py`

Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
diff --git a/tests/suites/test_suite_dhm.function b/tests/suites/test_suite_dhm.function
index bc43016..db88daa 100644
--- a/tests/suites/test_suite_dhm.function
+++ b/tests/suites/test_suite_dhm.function
@@ -15,7 +15,7 @@
 
 exit:
     mbedtls_mpi_free( &actual );
-    return( ok );
+    return ok ;
 }
 
 /* Sanity checks on a Diffie-Hellman parameter: check the length-value
@@ -47,7 +47,7 @@
     ok = 1;
 exit:
     mbedtls_mpi_free( &actual );
-    return( ok );
+    return ok ;
 }
 
 /* Sanity checks on Diffie-Hellman parameters: syntax, range, and comparison
@@ -75,9 +75,9 @@
         goto exit;
     TEST_EQUAL( offset, ske_len );
 
-    return( 1 );
+    return 1 ;
 exit:
-    return( 0 );
+    return 0 ;
 }
 
 /* END_HEADER */