i965: remove unneeded src_reg copy in emit_shader_time_write
i965: remove unneeded src_reg copy in emit_shader_time_write

The variable is already of type src_reg. creating a new instance only to
destroy it seems unnecessary.

Signed-off-by: Emil Velikov <f20878473f414da183da19ee25c8722cc1d711e4@collabora.com>
Reviewed-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler