d.legend.vect: Fix dead store warnings in draw.c

[ShubhamDesai]

This pull request addresses dead store warnings in the d.legend.vect module's draw.c file.

Fixed Issues:

• Warning: Value stored to 'symb_name' is never read.
• Warning: Value stored to 'label' is never read.

Changes Made:

• Commented out the redundant assignment to symb_name: // symb_name = G_store(tokens[1]);

• Commented out the redundant assignment to label: // label = G_malloc(GNAME_MAX);

[HuidaeCho]

Looks good to me.