make max_files in SD_MMC accessible by begin function

[Jilbers]

Related area

SD_MMC

Hardware specification

ESP32

Is your feature request related to a problem?

I must have more than 5 files open at the same time but the SD_MMC library doesn't allow this.
Instead max_files is set with a magic number.
It took me some time to find it. I didn't find any documentation about this limitation.

Describe the solution you'd like

When using the begin function a parameter where max_files can be set would be nice.

Describe alternatives you've considered

At the moment I call
esp_vfs_fat_sdmmc_mount("/sdcard", &host, &slot_config, &mount_config, NULL);
before begin with the same parameters as in the begin function but with max_files set to a higher number.

Additional context

No response

I have checked existing list of Feature requests and the Contribution Guide

• I confirm I have checked existing list of Feature requests and Contribution Guide.

[me-no-dev]

Fixed by @lbernstone in the PR above