spi_flash: fix race condition when doing operations in unpinned tasks

spi_flash: fix race condition when doing operations in unpinned tasks

spi_flash_enable_interrupts_caches_and_other_cpu function used to enable
non-IRAM interrupts after giving up flash operation lock, which would
cause problems if another task was waiting on the lock to start a flash
operation. In fact, non-IRAM interrupts should be re-enabled before the
task scheduler is resumed. Otherwise non-pinned task can be moved to the
other CPU due to preemption, causing esp_intr_noniram_enable to be
called on the other CPU, causing an abort to be triggered.

Fixes the issue reported in
https://github.com/espressif/esp-idf/pull/258