mmc: correctly check ret in mmc_fill_device_info

In patch 93768644, ret will be MMC_STATE_TRAN (=4), which is a valid value.
We shouldn't exit the function in that case, but only if ret is < 0.

Change-Id: I776693fe847b6b45190af028f12d2e724ca46399
Signed-off-by: Yann Gautier <yann.gautier@st.com>
1 file changed