unit: use g_assert_cmpstr()

Comparisons of simple values should use test macros instead of checking
standard library call return value.  This prints more information:

g_assert():
    ERROR:unit/test-ndef-parse.c:256:test_ndef_text_encoding: assertion failed: (strcmp(record->text->language_code, "en-US1") == 0)

g_assert_cmpstr():
    ERROR:unit/test-ndef-parse.c:256:test_ndef_text_encoding: assertion failed (record->text->language_code == "en-US1"): ("en-US" == "en-US1")

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
1 file changed