tests: add basic checks for inject=SET:syscall= expression syntax

tests: add basic checks for inject=SET:syscall= expression syntax

* tests/qual_fault-syscall.test: New test.
* tests/qual_inject-error-signal-syscall.test: Likewise.
* tests/qual_inject-retval-syscall.test: Likewise.
* tests/qual_inject-signal-syscall.test: Likewise.
* tests/Makefile.am (MISC_TESTS): Add them.
* tests/qual_fault-syntax.test: Add checks for inject=SET:syscall=
expression syntax.
* tests/qual_inject-syntax.test: Likewise.
* tests/qual_fault.test: Append $suffix to -e fault arguments, override
$NAME with $name_override if the latter is set.
* tests/qual_inject-error-signal.test: Append $suffix to -e inject
arguments, override $NAME with $name_override if the latter is set.
* tests/qual_inject-retval.test: Likewise.
* tests/qual_inject-signal.test: Likewise.