icc: Print each tag signature's spec name

The spec names are still a bit cryptic ("deviceMfgDescTag"
for "device manufacturer description"), but less cryptic than
just the fourcc.

There's a private tag area, so this will only print the spec name
of tags in the current spec. Private tags are in active use, e.g.:

    $ icc /Library/ColorSync/Profiles/WebSafeColors.icc
    ...
    Unknown tag ('dscm'): type 'mluc', offset 312, size 1490

(That's a v2 file. In v2, 'desc' has that strange textDescriptionType.
In v4, 'desc' has type 'mluc' -- but in v2, it didn't yet, so Apple
invented the private 'dscm' tag which has the description as an 'mluc'.)

Userland/Libraries/LibGfx/ICCProfile.h

@@ -114,7 +114,7 @@ URL device_model_url(DeviceModel);
     TAG(viewingCondDescTag, 0x76756564 /* 'vued' */)                \
     TAG(viewingConditionsTag, 0x76696577 /* 'view' */)
 
-#define TAG(name, id) constexpr TagSignature name { id };
+#define TAG(name, id) constexpr inline TagSignature name { id };
 ENUMERATE_TAG_SIGNATURES(TAG)
 #undef TAG