tg3: inline tg3_cond_int()

This patch inlines the code of tg3_cond_int() into the function's only
callsite.  This prep work makes the following patch cleaner.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>